Name: ___________________________________ Learning Group: _______

Matter and Mixtures Lab Safety and WHMIS:

Use resources (science textbooks, internet) to answer these questions.

1) What does “WHMIS” stand for?

2) What do these WHMIS symbols mean?

3) Why is the WHMIS system important?

4) Give a reason why each of the 5 following lab safety rules is important.

1 - Never begin an experiment or lab without your teacher’s permission.

2 - Keep your safety goggles on as long as there are any chemicals being used in the lab, even if you are finished.

3 - Never eat, drink, or chew gum during a lab.

4 - Report any injuries, no matter how minor, to your teacher.

5 - Follow instructions carefully and never perform experiments that are not intended.

Mix and Flow of Matter

Topic 1 – Types of Matter:

What is matter? Matter is anything that takes up space and has mass. There are three states of matter: solid, liquid and gas.

Solid Liquid GasAn object with a solid state of matter has a definite shape and volume.

The particles in a solid cannot move freely and are packed tight together.

Liquids have definite volume but not definite shape.

The particles in a liquid can pull away from one another and slip past one another. They do not form distinct clumps and they take the shape of the container that they are in.

Gases have neither a definite shape nor volume.

The particles in a gas are far apart from one another. They take on the shape and the volume of any container that they are sealed in.

The Particle Theory of Matter has the following rules:

1) Everything is made of tiny particles (or things).2) In a pure substance all the particles are the same.3) Particles have spaces between one them.4) Particles are always in motion. (the speed is

determined by the temperature, speeding up when the temperature increases and slowing down when the temperature decreases)

5) Particles are attracted to one another. This force depends on the type of particle.

Fluids: A fluid is anything that flows. It includes liquids and gases.

Questions:1. A substance has the volume and shape of the container it is in. Is the substance a solid,

liquid or a gas?

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2. Use the particle model to explain why ice cubes form in your freezer. (hint: talk about temperature and particles)

3. Describe a place or a situation where you could find water as a solid, liquid and gas at the same time. Explain.

4. What is sublimation?

5. Explain why solids can support objects more easily than fluids can. (hint: talk about their particles)

Topic 2 - Mixing and Dissolving:

Pure Substances can exist in the three states of matter. Each pure substance has its own set of physical properties such as colour, odour and hardness. It contains only one type of particle.

Elements and compounds are both pure substances. The particles of elements only have one type of atom in them. The particles of compounds have more than one type of atom in them.

Homogeneous Mixtures appear to be one substance, with particles of different substances mixed together.

Solutions are homogeneous mixtures in which no settling occurs overtime. The particles of one substance slip in between the particles of another substance and are dispersed evenly throughout the entire mixture.

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Heterogeneous Mixtures have two or more parts that can easily be seen. Another name for a Heterogeneous Mixture is a mechanical mixture.

Dissolving:

During the process of dissolving, the solvent is the substance that dissolves a solute in order to form a solution.

Water is know as the Universal Solvent because it dissolves so many materials.

How fast a solute dissolves is called the rate of dissolving. When you stir or agitate a mixture you can help the solute to dissolve faster. Another way to help the solute dissolve faster is by making the solute smaller.

A Saturated Solution will not allow any more solute to be dissolved in it, whereas an unsaturated solution can allow more of the solute to be dissolved in it.

Supersaturated Solutions contains more solute than would normally dissolve in a solvent.

All Matter (solid, liquid

gas)

Pure Substances

Elements

Compounds

Mixtures

Homogeneous

Solution

Heterogeneous (Mechanical

Mixture)

Suspension

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Questions:

1. Identify the following mixtures as heterogeneous, homogeneous, or both. Explain your reasoning for each.

a. coffee

b. ink

c. dirt

d. marshmallow

e. grape soft drink

f. milkshake

2. What is a solution? What evidence do you need in order to classify a material as a solution?

3. What does rate of dissolving mean? What are two factors that can change the rate at which a solid dissolves in a liquid?

4. Complete the table below:

Mixture Do the substances dissolve? (Write YES or NO)

If the substances dissolved,name the solute (or solutes)

name the solvent

1 sugar water

2 muddy water

3 salty water

4 pebbles in water

5 instant coffee drink

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6 orange juice

7 oil and water

8 iced tea drink

9 ocean water

10 vegetable soup

5. A cloud is a mixture of water droplets suspended in air. Is a cloud homogeneous or heterogeneous? Give reasons to support your answer.

Topic 3 - Separating Mixtures:

We often need to separate mixtures so that we can recover what we need. We can do this by using different separation methods. Here are a few examples:

- dehydration is the process of removing water from a solution. A lot of convenience foods come in a dehydrated form, like: soups, pasta mixes, juice crystals, etc.

- filtration uses a filter to separate a mixture.- distillation allows us to separate liquid from liquid (for example, water and saltwater

or petroleum products).

Questions:

1. Think of a strategy to separate each of these mixtures. Explain.a. oil and waterb. paper clips and penniesc. sawdust and sugar

Topic 4 - Flow Rate and Viscosity:

What is a fluid? A fluid is simply anything that can flow. (This includes liquids and gases.)

Flow Rate and Viscosity:- Viscosity is a liquid's thickness, or resistance to flow.- Liquids that are thicker than others are more viscous. - Flow rate is a measure of a liquid's viscosity.

- The flow rate of a fluid is measured in ml/s (milliliters per

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Mix and Flow of Matter

second).- By measuring the flow rate, we are able to compare the viscosity of different fluids. - The thicker the fluid, the slower it flows and the more viscous it is.

Changing Viscosity: Temperature affects the viscosity of fluids.

Fluid Liquid GasViscosity and Temperature

the viscosity of a liquid DECREASES as it is HEATED, and INCREASES as it is COOLED.

the viscosity of a gas INCREASES as it is HEATED, and DECREASES as it is COOLED.

Why? When heat is added to a liquid, the particles move faster and spread farther apart. Since the distance between particles has increased, there is less attraction between the particles. This allows the particles to move past each other more freely. As the temperature of a liquid increases, its viscosity decreases. As a result, the fluid flows more easily. The warmer the liquid, the faster it flows. As the temperature of a liquid decreases, the particles slow down. The result is that the viscosity increases. The cooler the liquid, the slower it flows.

Gases flow differently than liquids. Gas particles are so far apart that the attractive forces are low. They are more likely to run into each other than rub up against each other. Because of this difference, as temperature in a gas increases, the particles gain energy and move around quickly. They move around in all directions and collide more. These collisions cause more internal friction and the viscosity of the gas increases because it cannot flow as easily.

Practical Applications:People in many occupations need to know how to adjust the viscosity of a substance to suit specific applications. For example:

- chefs need to know how to make gravies, sauces, icing , etc. that are the right thickness- mechanics need to choose the engine oil that is the right viscosity- artists need to know how to thin or thicken oil paints or acrylics- technicians need to control the viscosity of chemicals in processing plants- oil needs to be the right viscosity to travel through pipelines- Food manufacturers need to make sure that their food is the right viscosity

Think:1. What is the effect of temperature on the flow rate – and thus viscosity – of a liquid? Explain using

the particle model.

2. What is the effect of temperature on the viscosity of gases? Explain using the particle model.

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3. Asphalt is the black, sticky material that binds gravel in the pavement that covers streets and highways. Explain why paving is almost always done in the summer months.

Topic 5 – Density:

Density is the “crowdedness” of the particles that make up matter.Scientific Definition: It is the mass per unit volume of a substance.

Density depends on the weight of the individual atoms and molecules making up the object, and how much space there is between them. Density also depends on whether the object is solid, filled with air pockets, or something in between.

Term Definition Unitsmass the amount of matter in a substance grams (g)volume the amount of space taken up by a substance millilitres (mL) – liquid/gas

centimetres cubed (cm3) - solidweight the force of gravity exerted on an object newton (N)gravity a natural force that cases an object to move

towards the centre of the earthnewton (N)

density the mass per unit volume of a substance g/mL – liquids OR g/cm3 – solids

Topic 6 – Buoyancy:

Buoyancy is the tendency for materials to rise or float in a liquid. The buoyant force is the upward force exerted of objects submerged in fluids.

Floating happens when an object is suspended in fluid. The force of gravity pulls down on an object, but the buoyant force pushes upwards, away from the Earth.

Buoyant forces are measured in Newtons, like other forces.

We look at average density when we are looking at things that float or sink. The average density of a ship (made out of metal, but filled with air) is less than that of water. The average density looks at the total mass of EVERYTHING on board a ship divided by the total volume.

Archimedes Principle:

An object that is partly or completely submerged in a fluidwill experience a buoyant forceequal to the weight of the fluid the object displaces.

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According to legend, it is said that Archimedes, a Greek inventor, who lived in the third century, discovered his principle after noticing that his bath overflowed when he got into it. He ran through the streets naked, shouting "Eureka!" ("I've got it!"). With this principle, he helped to prove that the King's goldsmith had tried to cheat him by putting silver into a gold crown. Archimedes also made discoveries in hydrostatics (science of stationary fluids), geometry, and mechanics (science of machines).

The buoyant force of a fluid depends on its density.The more dense a fluid is, the more buoyant force it will exert!

Think: 1. How could you make plastic sink and steel float?

2. What is Archimedes principle?

Topic 7 – Fluid Pressure:

Pressure is simply the force experienced by an object divided by the area of the surface on which the force acts. The unit for pressure is the pascal, Pa. Pressure is measured by dividing the amount of force, by the area where the force is applied.

P = F / A

Compressibility is the ability to decrease the volume of a fluid when pressure is applied.- Gases are highly compressible. As pressure increases, the volume of the gas decreases.- Liquids are nearly incompressible. As the pressure on the liquid increases, the volume remains

unchanged. - Because the particles in a liquid are already almost as close together as they can get, the

volume does not change, and the pressure is exerted everywhere on the container's inner surface.

Solids and liquids are almost incompressible. When we apply pressure to them, the pressure is passed on from particle to particle. Only the particles that have somewhere to move will move.

Atmospheric Pressure:

When we say atmospheric pressure, we're describing the pressure exerted by the weight of the air above us. The air goes up a long way, so even though it has a low density it still exerts a lot of pressure.On every square meter at the Earth's surface, the atmosphere exerts about 1.0 x 105 N of force. This is very large, but it is not

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Mix and Flow of Matter

usually noticed because there is generally air both inside and outside of things, so the forces applied by the atmosphere on each side of an object balance.

If the inside of a container experiences a lower air pressure than the air pressure pushing on the outside, this is an unbalanced forces, and the walls of the container will buckle and cave in.

Think:1. What is the difference between balanced and unbalanced forces?

2. What is pressure? What unit do we use to measure it?

Topic 8 - Fluid Systems:

Fluid systems are mechanisms that work because of the movement of a fluid, or the force exerted by a fluid within a closed system.

If this fluid is a liquid, the system is called a hydraulic system. Hydraulics is the study of pressure in liquids.

Think of the pipe system that is used to get your water to your tap.

If the fluid used is a gas, the system is called a pneumatic system. Pneumatic systems use compressors, which are devices that compress air.

Think of air brakes and gas pipelines.

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