class ‐ vii · class ‐ vii s. no. category topic page no. 1. syllabus guide line 04 2. explore...

CLASS ‐ VII S. No. Category Topic Page No.

1. Syllabus Guide Line 04

2. Explore & Experiment Light 07

3. Discover See Inside an Egg 12

4. Discover Balloon Blow UP 13

5. Invent Stir Up a Cyclone 15

6. Experiment Bottled Tornado 17

7. Discover Crystal Cartoon 19

8. Experiment Hot Air Magic 21

9. Experiment & Explore Make a Thermometer 22

10. Activity Pendulum Art 25

11. Explore Sound 27

12. Invent Chemical Magic 29

13. Activity Acid and Bases 32

14. Experiment Colour a Flower 34

15. Activity Science Play 35

16. Experiment Popping Rockets 36

17. Discover Heat Generating Steel Wool 37

18. Interactive Activity Acid and Bases 39

19. Activity Food Factory of Plants 43

20. Experiment Sky in Jar 44

21. Experiment Respiratory System 45

4 Class - VII Eduheal Foundation

Ques t ions

1. Food Sources of food What are the various sources of our food?

Utilisation of food How do plants and animals utilise their food?

2. Materials Materials of daily use Do some of our clothes come from animal sources? Which are these animals? Who rears them? Which part of the animals yield the yarn? How is the yarn extracted? What kinds of clothes help us to keep warm? What is heat? What is the meaning of ‘cool’/’cold’ and ‘warm’ hot? How does heat flow from/to our body to / from the surroundings?

Different kinds of materials Why does turmeric stain become red on applying soap?

How things change/react with one another What gets deposited on a tawa/kburpti/kudal if left in a moise state? Why does the exposed surface of a cut bringal become black?

Why is seawater salty? Is it possible to separate salt from seawater?

Key concepts

Plant parts and animal products as sources of food; herbivores, carnivores, omnivores.

Types of nutrition, nutrition in amoeba and human beings, Digestive system human, ruminants; types of teeth; link with transport and respiration.

Wool, silkanimal fibres. Process of extraction of silk, associated health problems.

Heat flow; temperature.

Classification of substances into acidic, basic and neutral; indicators.

Chemical substances; in a chemical reaction a new substance is formed.

Substance can be separated by crystallisation.

Activities/ Processes

Germination of seeds such as mung, chick pea etc.; preparing a chart on food habits of animals and food culture of different regions of India.

Effect of saliva on starch, permanent slide of Amoeba. Role play with children.

Collection of different samples of woollen and silk cloth. Activities to differentiate natural silk and wool from artificial fibres. Discussion

Experiment to show that ‘hot’ and ‘cold’ are relative. Experiments to show conduction, convection and radiation.

Testing solutions of common substances like sugar, salt, vinegar, lime juice etc. with turmeric, litmus, china rose. Activity to show neutralisation.

Experiments involving chemical reactions like rusting of iron, neutralisation (vinegar and baking soda), displacement of Cu from CuSO 4 etc. Introduce chemical formulae without explaining them.

Making crystals of easily available substances like urea, alum, copper sulphate etc. using supersaturated solutions and evaporation.

CLASS VII SYLLABUS GUIDELINES*

* Kindly note that Syllabus guidelines are given for present class but 90% question paper of NISO will be based on previous class syllabus.

Class - VII 5 Eduheal Foundation

3. The World of the Living Surroundings affect the living Why are nights cooler? How does having winters and summers affect soil? Are all soils similar? Can we make a pot similar? Can we make a pot with sand? Is soil similar when you dig into the ground? What happens to water when it falls on the cemented/bare ground?

The breath of life Why do we/animals breathe? Do plants also breathe? Do they also respire? How do plants / animals live in water?

Movement of substances How does water move in plants? How is food transported in plants? Why do animals drink water? Why do we sweat? Why and how is there blood in all part of the body? Why is blood red? Do all animals have blood? What is there in urine?

Multiplication in plants Why are some plant parts like potato, onion swollen are they of any use to the plants? What is the function of flowers? How are fruits and seed formed? How are they dispersed?

4. Moving Things, People and Ideas Moving objects Why do people feel the need to measure time? How do we know how fast something is moving?

5. How Things Work Electric current and circuits How can we conveniently represent an electric circuit? Why does a bulb get hot?

How does a fuse work?

Climate, soil types, soil profile, absorption of water in soil suitability for crops, adaptation of animals to different climates.

Respiration in plants and animals.

Herbs, shrubs, trees; Transport of food and water in plants; circulatory and excretion system in animals; sweating.

Vegetative, asexual and sexual reproduction in plants, pollination cross, self pollination; pollinators, fertilisation, fruit, seed.

Appreciation of idea of time and need to measure it Measurement of time using periodic events. Idea of speed of moving objectsslow and fast motion along a straight line.

Electric circuit symbols for different elements of circuit. Heating effect of current.

Principle of fuse.

Graph for daily changes in temperature, day length humidity etc.; texture of various soils by wetting and rolling; absorption/percolation of water in different soils, which soil can hold more water.

Experiment to show plants and animals respire; rate of breathing, what do we breathe out? What do plants ‘breathe’ out? Respiration in seeds; heat release due to respiration. Anaerobic respiration, root respiration.

Traslocation of water in stems, demonstration of transpiration, measurement of pulse rate, exercise etc. Discussion on dialysis, importance; experiment on dialysis using egg membrane.

Study of tuber, corm, bulb etc; budding in yeast, T.S./L.S. ovaries, w.m. pollen grains; comparison of wind pollinated and insect pollinated flowers; observing fruit and seed development in some plants; collection and discussion of fruits/seeds dispersed by different means.

Observing and analysing motion(slow or fast) of common objects on land, in air, water and space. Measuring the distance covered by objects moving on a road in a given time and calculating their speeds. Plotting distance vs. time graphs for uniform motion. Measuring the time taken by moving objects to cover a given distance and calculating their speeds. Constancy of time period of a pendulum.

Drawing circuit diagrams.

Activities to show the heating effect of electric current.

Making a fuse


How does the current in a wire affect the direction of a compass needle? What is an electromagnet?

How does an electric bell work?

6. Natural Phenomena Rain, thunder and lightning What causes storms? What are the effects of storms? Why are roofs blown off?

Light Can we see a source of light through a bent tube?

How can we throw sunlight on a wall?

What things given image that are magnified or diminished in size?

How can we make a coloured disc appear white?

7.Natural Resources Scarcity of water Where and how do you get water for your domestic needs? Is it enough? Is there rough water for agricultural needs? What happens to plants when there is not enough water for plants? Where does a plant go when it dies?

Forest products What are the products we get from forests? Do other animals also benefit from forests?What will happen if forests disappear?

Waste Management Where does dirty water from your house go? Have you seen a drain? Does the water stand in it sometimes? does this have any harmful effect?

A currentcarrying wire has an effect on a magnet. A currentcarrying coil behaves like a magnet.

Working of an electric bell.

Highspeed winds and heavy rainfall have disastrous consequences for human and other life.

Rectilinear propagation of light.

Reflection, certain surfaces reflect light.

Real and virtual images.

White light is composed of many colours.

Water exists in various forms in nature. Scarcity of water and its effect on life.

Interdependence of plants and animals in forests. Forests contribute to purification of air and water.

Sewage; need for drainage/sewer systems that are closed.

Activity to show that a currentcarrying wire has an effect on a magnet. Making a simple electromagnet. Identifying situations in daily life where electromagnets are used. Demonstration of working of an electric bell.

Making wind speed and wind direction indicators. Activity to show “life”due to moving air. Discussion on effects of storms and possible safety measures.

Observation of the source of light through a straight tube, a bent tube.

Observing reflection of light on wall or white paper screen.

Open ended activities allowing children to explore images made by different objects, and recording observation. Focussed discussions on real and virtual images. Making the disc and rotating it.

Discussions. Case study of people living in conditions of extreme scarcity of water, how they use water in a judicious way. projects exploring various kinds of water resources that exist in nature in different regions in India; variations of water availability in different regions.

Case study of forests.

Survey of the neighbourhood, identifying locations with open drains, stagnant water, and possible contamination of ground water by sewage. Tracing the route of sewage in your building, and trying to understand whether there are any problems in sewage disposal.


Light is an essential part of our life. Without it, we couldn‛t see the world around us. Light is also an important form of energy on which we depend on every day. But how does light search us and how does it affect the way we see our world.

Like us light actually moves from one place to another. Of course, we don‛t see it moving because it‛s moves very very fast at 186,000 miles a second. Light is the fastest thing in the universe. Light always travel in straight lines, or rays unless it bends or bounces off an object surface. We saw light moving here and there through reflection, refraction and in every colour around us.

Let‛s talk about reflection

Rays of light reflect, or bounce off, objects just like a ball bounces on the ground. This reflection of light enables us to see everything around us. Take a look out of your window: you see everything in the natural world (that doesn‛t produce its own light) because it reflects the light of the Sun. We can see the Moon because the Sun‛s light is reflected off the Moon‛s surface.

Light can reflect in different ways, changing the way objects look. Light reflects more off light-coloured surfaces than dark- coloured ones. You also see different types of reflection when you see an image reflected in a mirror or a spoon. A flat mirror reflects an exact, though reversed, image of an object because the reflected light rays travel at parallel paths. But a convex surface, like the outside of a spoon, causes light rays to spread out, distorting the reflected image. What do you think happens when an image is reflected off a concave surface, like the inside of a spoon?

Light


Try seeing your image in the spoons on both outer and inner surfaces. Also you can use plate or bowl.

What You‛ll Need

1 torchlight

1 mirror What To Do Place the torchlight on a table and turn

off the lights in the room.

Now place a mirror in front of the beam of light.

What happens to the beam?

Now try to focus the beam of light on different objects in the room by turning only the mirror.

Now let us study refraction through another activity.

The speed of light isn‛t always the same. It actually slows down when it moves through some transparent materials, like glass or water. When light slows down, it changes direction. This “refraction” of light is the reason a straw in water looks bent or broken and why objects viewed through a glass bottle appear distorted.

In the same way light reflects differently off different surfaces, it also refracts differently depending on the shape of the material. This can make refraction very useful. For example, the curve of eyeglasses directs light rays into the eyes more effectively. Magnifying lenses also use refraction: the convex lens bends the light rays so the image appears larger.


What You’ll Need torchlight

wide-toothed comb

clear bottles or glasses

Water

Cooking oil

Construction paper (optional)

What To Do Place the torchlight on the table and lean the

comb against it.

Turn the torchlight on and turn off the lights in the room. Notice the light beams that are shinning through the comb‛s teeth. (NOTE: If you cannot see distinct, individual light beams, try wrapping a piece of construction paper around the end of the flashlight. This will help direct and focus the light beam.)

Fill the small glass bottle or glass halfway with water and place it in front of the beams of light shining through the comb‛s teeth.

l What happens to the beams of light?

l Do the beams of light change direction?

l A focal point is where beams of light meet. Where is the focal point?


Try This Now fill your glass bottle or glass with cooking oil instead of water and try the experiment again. Are the results the same? Do the light beams refract differently through the cooking oil than in water? Is the focal point the same?

Have you heard white light? White light is a combination of all colours in the colour spectrum. It has all the colours of the rainbow. Combining primary colours of light like red, blue, and green creates secondary colours: yellow, cyan, and magenta. All other colours can be broken down into different combinations of the three primary colours.

Objects appear one colour or another because of how they reflect and absorb certain colours of light. For example, a red flower looks red because it reflects red light and absorbs blue and green light. A yellow banana reflects red and green light, and absorbs the rest.

What You’ll Need 1 white paper cup

Red, green, and blue markers

Strand of brightly coloured Deepawali Light

1 pencil or pen What To Do Colour the inside of a white paper cup with the three primary

colours of light: red, blue, and green. Leave one of the stripes


white (There should be four equal stripes in red, blue, green, and white.)

Use a pencil to punch a hole in the bottom of the cup.

Plug in the strand of Deepawali lights. Take a red light from the strand and stick it through the hole in the bottom of the cup.

Look at the red, blue, and green sections in the cup. For better results, turn off the room light.

l What happens to the colours inside the cup? Do they still look the same, or do the colours in the cup change?

More adventure Try the experiment using the blue and green lights. What happens to the colours inside the cup? Use what you learned about the colours of light to explain why the colours change.

I am an arachnida, climbing up the spout As you see, I‛ve eight legs - that‛s what I‛m all about

If I had just six legs I would be an insect. As surely you could tell!

Spiders are members of the arachnida family and are identified by the fact that they have eight legs. Insects are defined as having six legs and three body

parts (head, thorax and abdomen).


You must have eaten eggs... imagine a raw egg without the hard shell? Come lets do this experiment and see...

You Will Need

One raw egg (with shell)

Vinegar

Large bowl

Here’s how 1. Put a raw egg (in its shell) into a bowl and

cover it completely with vinegar.

2. Wait two days, then drain off the vinegar. When you touch the egg, it will feel rubbery. Be careful not to break the membrane, and wash your hands after you touch the egg. (Throw it away after the experiment.). Hold the egg and see. You can see the yolk moving up and down on moving the egg upside down. (Do it very carefully as the membrane is very delicate).

You Know Why? Vinegar is an acid which dissolves the calcium in the eggshell. It‛s calcium that makes the shell hard. But a thin, flexible membrane just under the shell still holds the egg‛s shape.

See Inside An Egg


What You’ll Need

A bottle with a narrow neck (preferably pepsi or coke bottle)

Vinegar

Baking soda

Funnel or straw

Water

Balloon

Here’s how ? 1 Pour about 15 cm of liquid— half vinegar and half water—into the bottle.

2 Use the funnel to fill the ballon half full of baking soda. (If you don‛t have a funnel, you can use a straw to load the balloon. Stick the straw into the baking soda, and put your finger over the top of the straw. Lift the straw out, put it into the balloon, and blow or tap gently.)

Balloon Blow‐Up!


3 Stretch the open end of the balloon over the neck of the bottle. Make sure it‛s tight! Let the heavy end of the balloon droop down, so no baking soda goes in the bottle.

4 Hold onto the ballon at the bottle neck, and pick up the heavy part of the balloon so that all the baking soda falls into the vinegar at the bottom of the bottle.

5 Wow! Hear the fizz? There are thousands of bubbles! And look at what‛s happening to the balloon...

Wow! I didn’t know that! Fizzy liquids like cold drinks get into your tummy faster than other liquids. The bubbles in soda tickle the tummy and make you burp!

DANCING RAISINS Now that your can of soft drink soda (eno will also do) is open, pour it into a glass. Drop in five or six small raisins. Watch tiny bubbles form all over them. In a minute or so, the raisins will start to wiggle around and dance. Then they‛ll float up to the top of the soda. After a minute, they‛ll sink back down again. If you tap on the side of glass, they‛ll sink right away. How long will they keep dancing?


Cyclones are huge circular storms of wind, clouds, and rain that form over warm tropical oceans. The clouds in a cyclone can be seen as circular bands that spiral around a cyclone‛s eye.

The word hurricane is used for cyclone in the United States and West Indies. In Japan & China sea these storms are called typhoons and in the Indian Ocean, they are called cyclones. In Australia they are called willy-willies.

Why do Hurricanes form? Why is it important that they form? The tropical cyclones role is to take heat stored in the ocean and transfer it to the upper atmosphere where upper level winds carry the heat to the poles. This is important because it is what keeps the Polar Regions from being cold as can be and keeping tropics from overheating.

Tropical cyclones help regulate the earths temperature. There- fore, it would not be wise to disrupt a cyclone‛s intensity because oceans will retain that heat. Over time, a heat build-up could enhance successive storm and increase their frequency and intensity.

Strength of a Cyclone Once a tropical cyclone system with organized circulation forms, it can become more organized if it stays over warm waters and upper level winds (wind shear) remain weak. Key to its power is warm water and warm moist air. A storm is propagated when

Stir up a Cyclone


water vapor cools and rises. It con- denses into clouds, releasing heat which warms the surrounding atmosphere. The air becomes lighter and continues to rise and more air rushes in its place, which are the strong winds we feel from storms.

When the eye of the storm moves over land, it lacks the moisture and heat that power the storm and convection. It weakens and eventually diminishes.

Here we are going to develop a cyclone at home! Don‛t panic, it is not disastrous. Come lets do & see.

You will need Large round bowl or tub of water Spoon Food colouring with a dropper top

Here’s How 1. Moving the spoon in a circular motion around the side of a bowl,

stir the water.

2. When the water is moving fast, stop stirring and immediately put several drops of food colouring into the centre of the swirling water. The colour will move out from the centre forming bands—much as clouds in a hurricane or cyclone do.

Convection that Powers Tropical Cyclones


Tornadoes don‛t travel as far or get as big as hurricanes, but their powerful, twisting winds are the fastest and most dangerous on Earth. At the centre of the tornado is a spinning column of air called vortex. This project lets you see what a tornado‛s vortex looks like.

You Will Need Two empty one-litre soft drink bottles, rinsed out and with

labels removed

Rubber or steel washer that has a small hole and is the same width as the opening of the bottles

Roll of strong electrical tape

Water

Here’s How 1. Tape the washer to the top

of either bottle, as shown. (Make sure the tape doesn‛t cover the hole in the washer.)

2. Fill that bottle three- fourths full of water.

Bottled Tornado


3. Place the empty bottle upside down on top of the washer. Tape the bottles securely together.

4. Turn the bottles over so that the one on top holds the water. Quickly swirl the bottles in a big circle several times and place the bottom bottle on a flat surface.

5. When you stop, the water should start swirling down in a tornado-shaped funnel, forming a vortex as the water drains into the lower bottle.

You Know Why? Have you ever seen a whirling funnel of water going down the drain of your sink that was earlier blocked? That whirlpool is called a water vortex. A vortex is a mass of fluid that moves in a circular motion to form a vacuum in its center. A vortex works with water much the same way a tornado works with air. A vacuum action tends to draw everything around a vortex toward its center.

WATER STRIDERS Water striders are insects that glide on the water‛s surface. Their legs stay on top of the water through surface tension. Air is trapped on hairs at the ends of the legs of the water striders, keeping their legs from falling into the water. If you look at one floating on the water, it looks like the ends of its legs are resting on little floating pads. These are actually small dents in the surface of the water made by the weight of the insect pushing down. Water bugs help the ecosystem. Some eat algae, which helps keep the amount of algae from becoming too high. They also provide food for other creatures.


Have you seen crystals? They look very beautiful. In this experiment you will make crystals at your home!

You Will Need?

Black chart paper Scissors A shallow bowl/pan Warm water Epsom salt

Tips for Home Scientists: This activity works best on a sunny day.

Here’s How

1 Use your scissors to cut the black paper so that it fits in the bottom of your pan.

2 Add 1 tablespoon of Epsom salt to 1/4 cup of warm water. Stir until the salt is dissolved.

3 Pour the salty water onto the black paper in the shallow bowl/pan.

4 Put the shallow bowl/pan out into the sun. When the water evaporates, you‛ll see lots of crystal spikes on the black paper!

Crystal Creations


Try This!

Do you know how that these crystals look great under a microscope. Try This

What’s Going On? Why does Epsom salt make crystal spikes?

When you add Epsom salt to water, the salt dissolves. When you leave the pan in the sun, the water evaporates and the salt forms crystals shaped like long needles.

If you tried this experiment with table salt instead of Epsom salt, you wouldn‛t get crystal spikes. That‛s because table salt and Epsom salt are chemically different, so the crystals that they form are very different.


You Will Need

one peeled, hard-boiled egg

plastic or glass bottle with an opening slightly smaller than the egg

large bowl of hot water

large bowl of ice water

Here’s how

1. Put the bottle in the bowl of hot water for about five minutes.

2. Move the bottle to the bowl of ice water. Wet the egg and place it pointed side down in the bottle opening. As the air inside the bottle cools, the egg will slowly move into the bottle.

3. To remove the egg, hold the bottle upside down so the egg is near the opening. Blow hard into the bottle with your mouth tight against the opening. Point the bottle away from you: The egg flies out!

You Know Why? Hot air expands. Cold air contracts. When the air inside the bottle is heated, the molecules, or tiny air particles, inside the bottle spread out, increasing air pressure. As the air in the bottle cools, the air pressure decreases. As the outside air pressure is greater, it pushes the egg into the bottle. Blowing into the bottle raises the air pressure again. The air and the egg rush out of the bottle.

Hot Air Magic


Watch how a simple thermometer works A thermometer is an instrument that measures the tempera-

ture. Temperature is measured in a scale. The point where water freezes is 32 degrees Fahrenheit (F) and 0 degrees Celsius (C). The point where water boils is 212 degrees F and 100 degrees C.

Some scientific thermometers use the Kelvin scale, where 0 Kelvin is called absolute zero - a place where there is no movement of any parts of matter, where substances have no thermal energy. It‛s about minus 273.15 degrees C (below 0° C) or 459.67 degrees below 0° F. Scientists have never been able to measure anything at absolute zero, though they have estimated very close.

Thermometers help us to know what the weather will be like. If it will be 90°F outside, we‛re not going to put on a winter coat. Or if it‛s below zero, we won‛t be wearing shorts.

Here‛s a way to show how a simple thermometer works.

Make a Thermometer

Changing Temperature Scales The Fahrenheit scale was named after Gabriel D. Fahrenheit. The Celsius scale was named after Anders Celsius. The Celsius scale is also called Centigrade. The Centi in centigrade means 1/100 (one one-hundredth) for the 100 equal divisions on the scale and is used by scientists. It is the temperature scale used by most of the world. The difference between the temperature where water freezes and boils is an even number of degrees...100. In the Fahrenheit scale, the difference between freezing (32° F) and boiling (212° F) is 180. Fahrenheit into Celsius Take your number; subtract 32° from it; and divide the remainder by 1.8. Example : Change 75 degrees Fahrenheit into Celsius.

75 - 32 = 43 43 / 1.8 = 23.88° C

So, 75° F is equal to 23.88° C Celsius to Fahrenheit Multiply your number by 1.8 and add 32° Example : Change 12 degrees Celsius into Fahrenheit.

12 x 1.8 = 21.6 21.6 + 32 = 53.6° F So, 12° C is equal to 53.6° F


What do you need? Tap water Rubbing alcohol (do not drink this) Clear, narrow-necked plastic bottle Food colouring Clear plastic drinking straw Modeling clay What to do? 1 Pour equal parts of tap water and rubbing alcohol into the bottle, filling about 1/8 to a 1/4 of the bottle. 2 Add a couple of drops of food colouring and mix. 3 Put the straw in the bottle, but don‛t let the straw touch the bottom (DO NOT DRINK THE MIXTURE). 4 Use the modeling clay to seal the neck of the bottle, so the straw stays in place. 5 Now hold your hands on the bottle and watch what happens to the mixture in the bottle. What you’ll discover! Congratulations!!! You just made a thermometer. Just like any thermometer, the mixture expanded when it was warmed. This made the liquid no longer fit in the bottom of the bottle. As the alcohol expanded the coloured mixture moved up through the straw. If the bottle were to get very hot, the liquid would have come through the top of the straw.


You can watch your thermometer and see how the liquid changes throughout the day.

What happens if your thermometer is in shadow or in sunlight?

What happens when it gets colder?

How does wind affect the thermometer?

Of course, in order to accurately read the temperature, you will need to buy a real thermometer that is carefully calibrated for temperature changes. This one is to see how a thermometer works — just for fun.

After you‛re done with your thermometer, dispose of the liquid properly and rinse the bottle well.

Why does a CD form rainbow colours? Like water drops in falling rain, the CD separates white light into all the colours that make it up. The colours you see reflecting from a CD are interference colours, like the shifting colours you see on a soap bubble.

You can think of light being made up of waves-like the waves in the ocean. When light waves reflect off the ridges on your CD, they overlap and interfere with each other. Sometimes the waves add together, making certain colours brighter, and sometimes they cancel each other, taking certain colours away.

When light reflects off or passes through something with many small ridges or scratcher, you often get rainbow colours and interesting patterns. These are called interference patterns.


If you suspend an object and give it a push, it will move back and forth at a regular rate.This action, called simple harmonic motion and the device, called simple pendulum, create some original art. The swing on which you play mostly in the park or the pendulum clock, are common examples showing simple harmonic motion.

You will Need (i) Paper, (ii) Black chart paper, (iii) Plastic funnel, (iv) Strings, (v) Common salt, (vi) Cellophane tape, (vii) Glue.

Here’s How 1. First make a paper cone to line the funnel. Cut a circle out of the paper. Remove a quarter (1/4 th ) of the circle, pull the sides together until they form a cone, and tape them. Leave a small hole at the tip.

2. Tie a string around the lip of the funnel. Use other string to suspend the funnel above the table. The funnel should hang a few centimeters above the table surface.

3. Place the black paper under the funnel, and put the paper cone into the funnel.

4. Block the funnel‛s tip with a finger and pour in some salt.

5. Remove your finger, push the funnel gently, and let it swing. The salt should form a pattern on the paper.

Pendulum Art


6. After the funnel stops, pour the salt back into the funnel. Try pushing off the funnel again in different ways and see what other patterns it forms.

7. To make a picture that you can save, brush a thin layer of glue over a large sheet of black paper, making sure that every area is covered. Then follow directions 4 and 5. Let your paper dry completely before removing it from the table.

Flaming Oranges Caution : This experiment uses flame! An adult must be

present during this experiment! Please be careful. You need: l A candle l Matches or lighter l Orange peel l Hands 1. Light the candle. 2. Get a piece of orange peel. 3. Hold the orange peel one or two inches from the candle

flame. 4. With the orange skin side facing the flame, bend and squeeze

the skin so liquid squirts towards the flame. 5. You should see a nice little flaming flare as you squirt the

orange skin juice! Be careful!


Everyday we hear thousands of different types of sounds — people talking, different types of music, honking of traffic, birds chirping, hustle and bustle of everyday life and lots more. All these are sounds. So, what is sound? How does it reaches our ears? Come, lets known more about sound.

What is Sound? Sound is a type of energy made by vibrations. When any object vibrates, it causes movement in the air particles. These particles bump into the particles close to them, which makes them vibrate too causing them to bump into more air particles. This movement, called sound waves, keeps going until they run out of energy. If your ear is within the range of the vibrations, you hear the sound.

Picture a stone thrown into a still body of water. The rings of waves expand indefinitely. The same is true with sound. Irregular repeating sound waves create noise, while regular repeating waves produce musical notes.

When the vibrations are fast, you hear a high note. When the vibrations are slow, it creates a low note. The sound waves in the diagram show the different frequencies for high and low notes.

Low Frequency notes High Frequency notes

Sound


How do Wind Instruments make sound? In wind instruments, like the flute and trumpet, vibrating air makes the sound. The air particles move back and forth creating sound waves. Blowing across a flute‛s blow hole sets up Slinky-like waves in the tube. In the flute, a vibrating reed (a thin piece of wood set in the mouthpiece) gets the waves started. Different pitches are played by pressing keys that open or close holes in the tube making the air column inside the tube longer or shorter. Longer air columns produce lower pitches.

How do String Instruments make sound? Stringed instruments are played by pressing the fingers down on the strings. This pressure changes the strings‛ length, causing them to vibrate at different frequencies and making different sounds. Shortening a string makes it sound higher. Strings produce different sounds depending on their thickness.

Can sound travel under the water? Yes sound can travel under the water. It moves four times faster through water than through the air. It can travel such long distances that whales can hear each other when they are nearly a hundred miles apart.

Is there sound on the moon? No, there is no sound in space. Sound needs something to travel through like air or water.

What is the speed of Sound? Sound travels through air at 340 metres per second.


Some of the earliest recorded “magic” were actually nothing more than a few simple science experiments using chemistry. Just imagine how amazed your friends would be if you could change crystal clear water into grape juice... and then into lemonade. Don‛t tell anyone that it‛s not really grape juice or lemonade. It‛s chemical magic and the ingredients are in your kitchen.

Make Your Own Cabbage Juice 1. Peel off six big cabbage leaves (red

cabbage) and put them in a blender filled half full with water. Liquify it!

2. Pour the purplish cabbage liquid through a strainer to filter out all of the big chunks of cabbage. Doesn‛t cabbage juice smell great?

3. Save the liquid for the experiments to follow.

What to do? This experiment will teach you how to make your own indicator using cabbage juice. The materials are different depending on the method you select. If you want to make your own indicator, you‛ll need a few leaves of red cabbage, a blender, a strainer, plastic cups, water and some household chemicals like vinegar, washing soda etc.

Chemical Magic


Regardless of which method you used to make your “indicator” solution, try this...

Set out three glasses, side by side against a white piece of paper. Fill each glass half full with cabbage juice. Since you know that vinegar is an example of an acid, add a little vinegar to the first glass of cabbage juice. Stir with a spoon and notice the colour change to red, which indicates that vinegar is classified as an acid. In the second glass add a teaspoon of washing soda or detergent. Notice how the liquid turns green which indicates this chemical is a base. Keep these two glasses of red and green liquid for future reference.

Try adding your own “test” substances to a small amount of cabbage juice and note the color change to determine if something is an acid or a base.

How does it work? Some substances are classified as either an acid or a base. Think of acids and bases as opposites - acids and bases are on opposite sides of a teeter-totter. Scientists can tell if a substance is an acid or a base by means of an indicator. An indicator is typically a chemical that changes colour if it comes in contact with an acid or a base. This experiment will teach you how to make your own indicator using cabbage juice.

As you can see, the purple cabbage juice turns red when it is mixed with something acidic (an acid), or green when it mixes with something basic (a base). In the experiment, the vinegar was the acid and the laundry detergent was the base. Remember that an acid is the opposite of a base. Red cabbage juice is considered to


be an indicator because it shows us something about the chemical composition of other substances. This is just one of many indicators that are available to scientists. Some indicators start out colourless and turn blue or pink, for example, when they mix with a base. There are hundreds of different types of indicators available to scientists depending on the type of substance that they are testing. If there is no color change at all, the substance that you are testing is probably neutral, just like water.

Use your cabbage juice indicator to test the acid or base properties of other common substances: Orange juice, lemonade, milk, salt, ammonia, or soap are some suggestions. You‛ve heard about how acid rain is destroying the environment. Collect a sample of rain water and test its acidity using your cabbage indicator.

TV Ghosts You need: l Television (not a LCD or plasma TV) l Flashlight 1. Turn off the TV. 2. Turn off the lights in your TV room. 3. Shine your flashlight at the TV for about 30 seconds to a

minute. 4. Now turn off the flashlight. 5. You should see a glowing spot on the TV where the flashlight

was pointed. A television screen has stuff in it that glows when it‛s hit with light. That‛s why you can see the shows on the TV screen. When you shine a light on the screen you cause it to glow for a little bit.


1. Alkalis turn litmus b __ __ __ .

They feel s __ __ __ __ to touch.

Many alkalis are too

d __ __ g __ __ __ __ __ to feel.

2. A neutral substance is neither acid nor alkali. Colour acids red, alkalis blue and neutral substances purple.

salt vinegar soap

lemon juice pure water tooth paste

oven cleaner fruit juice sugar

Sulphuric Acid Nitric Acid Hydrochloric Acid

paint

Cut out the pictures below and stick them in the correct column.

_________________________________________________

blue

dangerous

soapy

Acids and Bases


1. Universal indicator can tell us whether an acid or alkali is strong or weak.

strong acid weak acid neutral weak alkali strong alkali

1 2 3 4 5 6 7 8 9 10 11 12 13 14

red pink dark yellow yellow bright green green dark green/ blue darker dark purple yellow yellow green blue blue blue

2. What is it? Acid, alkali or neutral?

pH 2 pH 7 pH 2

Substance A It is__________ Its colour is____

Substance B It is__________ Its colour is____

Substance C It is__________ Its colour is____

3. Match the solution with its pH and its colour in universal indictor.

Substance pH colour

stomach acid pH 5-6 green

skin pH 1 yellow

soap pH 10 red

pure water pH 9 green-blue

milk of magnesia pH 7 dark green

Acids and Bases


You have seen beautiful, coloured flowers made by nature. But here you are going to make coloured flowers on your own. Come, lets do & see.

What you need (i) White flowers

(ii) A glass of water

(iii) Food colouring/colouring agent

What you do 1. Put a white carnation or vinca in a vase with 1/2 cup of water.

2. Mix 10 or more drops of food colouring into the water.

3. Leave the flower overnight, and you‛ll see the petals (the papery coloured part of the flower) change colours. If you leave the flower in the coloured water longer, more colour will fill the petals.

The food colouring travels up through the stem and reaches the flower‛s petals. If you look closely at the petals you can see the path that the food colour and water travel.

Colour a Flower


Science Play There are two mega questions which you need to answer. But to answer these mega questions first you have to solve the following crosswords.

1. Very common element found in living creatures

2. Genes are made of this 3. Meat eaters are at the top of

this 4. Plants need this to live 5. Basic unit of life 6. Life needs food to produce this 7. One of the three Kingdoms 8. Most or all life is based on this

liquid

1. Simplest plants 2. Mold, Mushroom or Yeast 3. Creature with a backbone 4. Instrument

used to see very small things

Mega question 1 These are Believed to be the Oldest Forms of Life.....

1

2

3

4

5

6

7

8

Mega question 2 These Creatures are Believed to be the most common on Earth.....


You must have heard about rockets launched by scientists. As you have young scientist activity book so you are also a young scientist and you too can launch your rocket at home ! Come lets do now.... Use baking soda and vinegar to create a chemical reaction which launches a rocket up in the sky ! What you will Need? Film canisters (plastic covers of film rolls) Baking soda (sodium bicarbonate) Vinegar (acetic acid) Here’s How? 1. Take the top off the film canister and pack the lid tightly with baking soda. 2. Pour about two teaspoons of vinegar into the film canister. 3. Gently put the lid on the film canister and snap closed. 4. Turn the canister upside-down, put it on the ground, and stand back. 5. After a few seconds, the canister will shoot up into the air. If your rocket always fizzles, try a film canister with a tighter- fitting lid. What’s Happening? You are creating a chemical reaction between the baking soda (NaHCO 3 ) and the vinegar (CH 3 COOH). The vinegar reacts with the baking soda, producing carbon dioxide gas (CO 2 ). Pressure builds up until the small canister can no longer contain the gas. The lid pops off, the canister shoots up into the air, the gas escapes, and the pressure is released.

Popping Rockets

Do this project outside. The reaction between baking soda and vinegar makes a mess! Plus your rocket is going to fly high! As soon as you put the lid on the film canister, move out of the way— it can blow fast!


Steel Wool generating heat The rust on the iron grills of your window or gate is a type of chemical reaction.

Chemical reactions occur every day all around us. A chemical reaction is a process where one type of substance is chemically converted to another substance. The fire in your fireplace is a type of chemical reaction. The smoke that comes out of Dad‛s ears when you lose one of his important official document is a result of a chemical reaction! OK, so may be that‛s a bad example, don‛t do that.

This experiment demonstrates a chemical reaction that‛s fairly common all around us.

1. Put the thermometer in the jar and close the lid. 2. Wait about 5 minutes and write down the temperature. 3. Remove the thermometer from the jar. 4. Soak a piece of steel wool in vinegar for one minute. 5. Squeeze the vinegar out of the steel wool pad. Wrap the steel

wool around the bulb of the thermometer. 6. Place the thermometer and steel wool back into the jar and

close the lid. 7. Wait 5 minutes. 8. Now take a look at the temperature.

What happened to the temperature? Are you surprised that the temperature rose (sorry this experiment didn‛t produce any smoke but then again, you didn‛t get grounded either).

Heat Generating Steel Wool


The vinegar removes any protective coating from the steel wool, allowing the iron in the steel to rust. Rusting is a slow combination of iron with oxygen. When this happens, heat energy is released. The heat released by the rusting of the iron causes the mercury in the thermometer to expand and rise.

Important Chemical reaction is a process in which one substance is chemically converted to another. All chemical reactions involve the formation or destruction of bonds between atoms (atoms, made up of protons and neutrons in a central nucleus surrounded electrons, are the smallest particle of a chemical element that can take part in a chemical reaction without being permanently changed). Chemical reactions include the rusting of iron and the digestion of food. Most chemical reactions give off heat (Such chemical reaction are called exothermic reaction). For example, chemical reactions that occur in digestion give off heat that keeps our bodies warm and functioning.

Answers Page 35

C A D N O O

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F L

D C

E R I A

A H

L G M T

A

L Y A L

R E

I N G

N A

H T C E N W

R B O N

A L G A E N G F U U S T E V A

E O B E T R R E

S M C I O C P R


Acids and Bases The degree of acidity or alkalinity (basic) is important in organisms. The body must constantly maintain a near neutral pH (7) in the blood and body tissues. To do this, the body produces buffers that can neutralize acids. Acidic and basic conditions in the body occur due to different metabolic reactions taking place throughout the body.

The force of attraction between molecules is so strong that the oxygen atom of one molecule can actually remove the hydrogen from other water molecules. This reaction is known as dissociation, and it takes place in our cells. Water (H 2 0) dissociates into H + and OH - ions. The OH - ion is called the hydroxide ion, while the H + ion is called the hydrogen ion. Free H + ions can react with another water molecule to form the H 3 O + or hydronium ion.

Acidity or alkalinity is a measure of the relative amount of H + and OH - ions dissolved in a solution. Neutral solutions have an equal number of H + and OH - ions. Acids have more H 3 O + ions than OH - ions. Acids taste sour and can be corrosive. Digestive fluids in the body are acidic and must be neutralized by buffers. Bases contain more OH - ions than H 3 O + ions. Bases taste bitter and feel slippery.

When an acid is combined with a base, neutralization occurs. The result of neutralization is a salt and water. Neutralization helps return our body pH to neutral. The process of our bodies maintaining neutral pH so that proteins can work properly without being denaturated (unfolded) is known as homeostasis.


Colour the following diagrams according to the key.

Dissociation of Water

Acids & Bases


Neutralization

Now answer the following questions :

1. What ions form when water dissociates? (a) Hydrogen ion (b) Hydronium ion (c) Hydroxide ion (d) (a) & (c)

2. Acids have an excess ofwhich of the following ions? (a) H

3 O + (b) H +

(c) OH – (d) All of these

3. Neutral solutions are those that have an equal no. of (a) H 3 O + and OH – ions (b) H + and H 3 O + ions (c) H 2 O and OH – ion (d) H + and OH – ions

4. What is produced by the body to help neutralize acidic conditions? (a) Salt (b) Water (c) Buffer (d) Digestive fluid

5. pH of our body returns to normal due to - (a) Homoestasis (b) Neutralization (c) Dissociation (d) Metabolic reactions

6. What is the name for the OH - ions?


________________________________________________

____________________________________________________________________________________________________________________________

7. What is the name for the H + ion? ____________________________________________________________________________________________________________________________

____________________________________________________________________________________________________________________________

8. How does the hydronium ion form? What is its formula? ____________________________________________________________________________________________________________________________

____________________________________________________________________________________________________________________________

9. Why do most proteins need near a neutral pH? ______________________________________________________________

____________________________________________________________________________________________________________________________

10. What two substances form from an acid-base neutralization? ______________________________________________________________

____________________________________________________________________________________________________________________________


Following is the diagram of Plant kitchen - leaf. Leaves are responsible for making food in the plant with the help of carbondioxide and water taken from environment. Cut the following resources and products and place them at their right position in plant kitchen.

Food Factory of Plants

carbon dioxide carbon dioxide Water

food oxygen oxygen

Complete the sentences using your knowledge.

1. During the day, p__________ make their own f________ in their l__________ using e__________ from the S_________.

2. This is called p___________________.

3. W_____________ and c_____________ d_____________ are needed to make the plants‛s food (s___________).

Draw the plants to show the way the plants will move in response to light.


Lets bring vast sky in a jar What you need: a clear, straight-sided drinking glass, or clear plastic or glass jar water, milk, measuring spoons, torch light a darkened room

What to do: Fill the glass or jar about 2/3 full of water Add 1/2 to 1 teaspoon (2 - 5 ml) milk and stir. Take the glass and flashlight into a darkened room.

Hold the flashlight above the surface of the water and observe the water in the glass from the side. It should have a slight bluish tint. Now, hold the torch light to the side of the glass and look through the water directly at the light. The water should have a slightly reddish tint. Put the torch light under the glass and look down into the water from the top. It should have a deeper reddish tint.

What happened: The small particles of milk suspended in the water scattered the light from the torch, like the dust particles and molecules in the air scatter sunlight. When the light shines in the top of the glass, the water looks blue because you see blue light scattered to the side. When you look through the water directly at the light, it appears red because some of the blue was removed by scattering.

Sky in jar


Respiration is the key function which a living thing perform. In this activity we will make some model to see how respiratory organs work. The general functions of the respiratory system is to deliver oxygen to the tissues, the importance of cellular respiration, the processes of inhalation/exhalation, determine the volume of air exhaled and to eliminate carbon dioxide formed in the body.

You will: Demonstrate that there is oxygen in the air we breathe. Build a model of the respiratory system. Measure the amount of air that can be forced out of the lungs. Demonstrate that carbon dioxide is exhaled from the body.

Part A

1. Candle 2. Matches 3. Pan 4. Clear cup or glass 5. Water

What to do : This experiment will show that there is oxygen in the air we breathe. 1. Place a small amount of water in the bottom of the pan, enough

to cover the bottom of the pan.

Respiratory System


2. Light the candle and place in the water on the bottom of the pan.

3. Cover the lit candle with the glass and observe what happens to the water.

Part B 1. 2-pieces of straw 2. 2-small balloons 3. rubber cement (adhesive) 4. 1-large balloon 5. rubber bands - 2 small, 1 large 6. tape

What to do : This model will show the action of the diaphragm in human respiration. 1. Take a piece of straw about 5 cm in

length and cut a small triangle in the center, but don‛t go through to the opposite side. Fit one small balloon over each end of the straw and secure it with a small rubber band. (Make sure that air will go into each balloon when blown from the top.)

2. Bend the straw in the middle of the hole. 3. Take a second piece of straw and cut a V-shape on the end. Fit

the slanted points of the straw into each semi-circle of the hole of the bent straw.

4. Cement the two pieces of the straw together. Allow to dry or use tape to hold until dry.


5. Cut a hole in the bottom of the clear plastic cup using the diameter of the straw as a guide to the size. Push the open end of the straw into the hole of the plastic cup from the inside. Cement the straw into the hole.

6. Take the large balloon and cut the neck off. Carefully stretch the cut balloon over the opening of the cup. Do not crack the cup. Secure the edges with the large rubber band. Do not cement the sides of the cup. The model will only work if there are no leaks.

7. Then pull the bottom balloon gently and observe what happens to the small balloons.

Part C 1. Lime powder 2. Water 3. Clear cup or glass 4. Straw

What to do : This experiment will show that carbon dioxide is one of the major cellular metabolic waste products. 1. Place about a teaspoon of lime powder in a cup or glass of

warm water and mix thoroughly. Cover the glass and let remain over night.

2. Next day drain the clear fluid off the top of the solution. This is the lime water for the experiment.

3. Place the straw in the lime water and blow into the straw. Observe what happens to the clear fluid.

Part D

1. Plastic dish pan


2. About 60 cm long aquarium tubing 3. 4 liters plastic milk jug 4. masking tape 5. pen 6. A large cup

What to do : This experiment will demonstrate lung capacity by measuring the amount of air that can be forced out of the lungs. 1. Place a strip of masking tape down the side of the milk jug from

the top to the bottom. 2. Fill the jug with water using a cup to measure amount of water

it takes to fill the jug. Mark each cup on the tape (these measurements will serve to show the amount of water exhaled) and screw on the cap.

3. Fill the dish pan about 1/2 full with water. 4. Place the jug upside down in the water, and remove the cap. 5. Have a helper hold the jug. DO NOT allow air bubbles to enter

the milk jug. 6. Place one end of the aquarium tubing inside the mouth of the

jug. 7. Take a normal breath and exhale through the tubing. Mark the

water level on the tape. 8. Refill the jug with water and return it to the dish pan. 9. Breath in deeply and make an effort to exhale all of the air in

your lungs through the tubing. Mark the water level on the tape.

class ‐ vii · class ‐ vii s. no. category topic page no. 1. syllabus guide line 04 2. explore...

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