lab equipment overview

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Triple Beam Balance Graduated Cylinder Ruler (metric) Ruler (standard) Meter Stick Spring Scale Thermometer Lab Equipment Overview

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Lab Equipment Overview. Triple Beam Balance Graduated Cylinder Ruler (metric) Ruler (standard) Meter Stick Spring Scale Thermometer. Triple Beam Balance (Overview). Used to measure mass Unit of measure: gram (g). Pan. Balance/Zero Mark. Zero Adjustment Knob (below pan). - PowerPoint PPT Presentation

TRANSCRIPT

Page 1: Lab Equipment Overview

Triple Beam BalanceGraduated Cylinder

Ruler (metric)Ruler (standard)

Meter StickSpring ScaleThermometer

Lab Equipment Overview

Page 2: Lab Equipment Overview

Triple Beam Balance(Overview)

• Used to measure mass• Unit of measure: gram (g)

PanBalance/Zero

Mark

Zero Adjustment

Knob(below pan)

3 Riders/Movable Masses(top-down = tens, hundreds, ones)

Page 3: Lab Equipment Overview

1. Place the balance on a flat, level surface.2. Move all sliders to the left (zero).3. Determine if the pointer is at the zero mark. If at the zero mark

move to step five – if not at the zero mark, complete step four. This should be done at eye level.

4. Turn the zero adjustment knob counter-clockwise (up) to have the pointer move upward or turn the knob clockwise (down) to have the pointer move downward – this knob should be adjusted until the pointer is at the zero mark.

5. Place the object on the pan.6. Move the largest slider (hundreds) to the right until the pointer

falls below zero – you should feel the slider click as it moves along. The slider must be “clicked” into place in order to get accurate measurements. You should move the slider one notch back after the pointer falls below zero.

7. Repeat step six with the tens slider.8. Move the ones slider to the right until the pointer is at the zero

mark.9. Determine the object’s mass, in grams, by totaling the

numerical values highlighted by the hundreds, tens, and ones sliders.

Triple Beam Balance(How to Use)

Page 4: Lab Equipment Overview

Triple Beam Balance (Example)

• What is the mass of the object being measured by the triple beam balance if the sliders/movable masses have the shown positions?

0 g (hundreds)

30 g (tens)

2 g (ones)+

32 g

Page 5: Lab Equipment Overview

Graduated Cylinder(Overview)

• Used to measure volume• Unit of measure: milliliter (mL)• Come in a variety of sizes • Value of graduated markings,

or lines, change as the size of the graduate changes

• Using the smallest possible graduated cylinder typically results in more accurate measurements

Each of these lines represent graduated

markings

Page 6: Lab Equipment Overview

Graduated Cylinder(Graduated Markings)

• To accurately determine volume when using a graduated cylinder, it is important to figure out the value of each graduated marking

• To do this:1. Calculate the difference

between two printed numbers 2. Count the number of divisions

between them3. Divide the difference (#1) by

the number of divisions (#2). In this case, the difference between 80 and 70 mL is 10 mL. If I then count the number of divisions between those two numbers I get 10. If I divide the 10 mL by the 10 divisions I get 1 mL per line.

What is the value of each line?

Page 7: Lab Equipment Overview

Graduated Cylinder(Meniscus)

• The meniscus is the curved line that the liquid makes inside of the graduated cylinder as a result of the adhesion and cohesion properties of the liquid

For this example, the volume of the liquid would be 62 mL since the

bottom of the meniscus falls on the 62 mL mark.

Meniscus

If each graduated marking has a value of 1 mL, what would be the volume of the liquid if you read the graduated cylinder from the bottom of

the meniscus?

Page 8: Lab Equipment Overview

Graduated Cylinder (How to Use - Liquids)

1. Select the smallest possible graduated cylinder that can accommodate the amount of liquid you will be measuring.

2. Determine the value of each graduated marking, or line, found on the graduated cylinder – knowing this will help you determine the volume.

3. Place the graduated cylinder on a flat, level surface.

4. Carefully pour the liquid into the graduated cylinder without spilling any.

5. Measure the level of the water by looking at the bottom of the meniscus. This should be done at eye level.

Page 9: Lab Equipment Overview

Graduated Cylinder (Example)

• What is the volume of the liquid in the graduated cylinder?

Meniscus

Since each graduated marking is equivalent to 1 mL, the volume of

the liquid in the graduated

cylinder is 48 mL

Page 10: Lab Equipment Overview

Graduated Cylinder (Water Displacement - Overview)

• Water displacement is a process by which a graduated cylinder is used to determine the volume of a solid object, particularly one that is irregularly shaped.

• The volume is calculated by observing the amount of water displaced by the submerged object.Initial Volume (water) Final Volume (water + rock)

Meniscus

Notice how the water level

rose after the object was

placed in. This rise of the

water helps you figure out the object’s

volume.

Page 11: Lab Equipment Overview

Graduated Cylinder (How to Use – Water Displacement)

1. Select the smallest possible graduated cylinder that can accommodate the object you will be measuring.

2. Determine the value of each graduated marking, or line, found on the graduated cylinder – knowing this will help you determine the volume.

3. Fill the graduated cylinder with enough water to adequately submerge the irregularly shaped object you will be measuring. However, do not fill it so much that water will rise past the graduated cylinder’s graduations when placing the irregularly shaped object in.

4. Place the graduated cylinder on a flat, level surface.5. Measure the level of the water by looking at the bottom of the

meniscus and record the volume (initial). This should be done at eye level.

6. Carefully place the irregularly shaped object into the graduated cylinder. This can be done by angling the graduated cylinder and allowing the object to gently slide down the side into the water.

7. Measure the new level of the water by looking at the bottom of the meniscus and record the volume (final). This should be done at eye level.

8. Calculate the volume of the irregularly shaped object by subtracting the initial volume (measured in step five) from the final volume (measured in step seven).

Page 12: Lab Equipment Overview

Graduated Cylinder (Water Displacement - Example)

• What is the volume of the rock in the graduated cylinder?

Initial Volume (water) Final Volume (water + rock)

Meniscus

28 mL 38 mL

38 mL (final volume)28 mL (initial volume)-

10 mL or 10 cm3

Page 13: Lab Equipment Overview

Ruler (metric)(Overview)

• Used to measure length/distance• Units of measure: centimeters (cm), millimeters

(mm)• Markings

– Each small (unnumbered) line is a millimeter division– Each long line followed by a number is a centimeter

division – 10 millimeters in a centimeter

1 mm 1 cm

Important – this is only a portion of a ruler

Page 14: Lab Equipment Overview

1. Choose an object to measure and place it on a flat surface.

2. Align the ruler to the side of the object with the beginning of the object at the zero mark. Be careful, some rulers have the zero mark at the starting edge and some have a zero mark slightly indented.

3. Locate the opposite edge of the object and read the last number on the ruler where the object ends.

Ruler(How to Use)

Page 15: Lab Equipment Overview

Ruler (metric) (Example)

• What is the length (millimeters and centimeters) of the object below?

37 mm

3.7 cm

What is the relationship between your two answers?

Page 16: Lab Equipment Overview

Ruler (standard)(Overview)

• Used to measure length/distance• Units of measure: inches (in), feet (ft)• Markings

– The smallest lines show divisions of 1/16th inch– The small lines show divisions of 1/8th inch– The medium lines show divisions of ¼ inch– The long lines show divisions of ½ inch– The long lines followed by a number

show divisions of 1 inch

Important – this is only a portion of a ruler

1/16th 1/8th 1/4 1/2

1

Page 17: Lab Equipment Overview

Ruler (standard)(Dissection)

Parts of an inch

16 Sixteenths

8 Eighths

4 Fourths

2 – Halves

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

1 2 3 4 5 6 7 8

1 2 3 4

1 2

CombiningEach Part 1/16”

1/8”

3/16”

1/4”

5/16”

3/8”

7/16”

1/2”

9/16”

5/8”

11/16”

3/4”

13/16”

7/8”

15/16”

1”

Page 18: Lab Equipment Overview

1. Choose an object to measure and place it on a flat surface.

2. Align the ruler to the side of the object with the beginning of the object at the zero mark. Be careful, some rulers have the zero mark at the starting edge and some have a zero mark slightly indented.

3. Locate the opposite edge of the object and read the last number on the ruler where the object ends.

Ruler(How to Use)

Page 19: Lab Equipment Overview

Ruler (standard) (Example)

• What is the length (inches) of the object below? Round to the nearest 1/16th of an inch.

1 7/16 inches

Page 20: Lab Equipment Overview

Meter Stick(Overview)

• Used to measure length/distance• Units of measure: meter (m), centimeter

(cm), millimeter (mm)• Markings

– Each small (unnumbered) line is a millimeter division– Each long line followed by a number is a centimeter

division – 10 millimeters in a centimeter – 100 centimeters in a meter

Important – this is only a portion of a meter stick

1 mm 1 cm

How many millimeters are in a meter?

Page 21: Lab Equipment Overview

1. Choose an object to measure and place it on a flat surface.

2. Align the meter stick to the side of the object with the beginning of the object at the zero mark. Be careful, some meter sticks have the zero mark at the starting edge and some have a zero mark slightly indented.

3. Locate the opposite edge of the object and read the last number on the meter stick where the object ends.

Meter Stick(How to Use)

Page 22: Lab Equipment Overview

Meter Stick (Example)

• What is the length (in meters, centimeters, and millimeters) of the object below?

0.246 m

24.6 cm

246 mm

Page 23: Lab Equipment Overview

Tubular Spring Scale(Overview)

• Used to measure weight• Units of measure: newton (N), gram (g)• Dependent on gravity• Come in a variety of

measurement capabilities (100g/1 N – 10,000g/100 N) - usually indicated by different colors for tubular scales

• Value of graduated markings, or lines, vary with the spring scale’s capacity

• Using a spring scale with the smallest possible capacity typically results in more accurate measurements

Ring

Pointer

Graduated Markings

Hook

Spring

AdjustmentNut

Page 24: Lab Equipment Overview

1. Select a spring scale with the smallest possible capacity that can accommodate, or measure, the weight of your object.

2. Determine what scale you will be using (newtons or grams).3. Similar to when using a graduated cylinder, determine the

value of each graduated marking, or line, found on the spring scale – knowing this will help you determine the weight.

4. Hang the ring of the spring scale on a sturdy object such as a ring stand (with clamp) if possible.

5. Determine if the pointer is at the zero mark. If at the zero mark move to step seven – if not at the zero mark, complete step six. This should be done at eye level.

6. Zero the spring scale by turning the adjustment nut at the top clockwise to raise the pointer and counter-clockwise to lower the pointer – the nut should be adjusted until the pointer is at the zero mark.

7. Carefully hang the object on the hook.8. Measure the object’s weight by reading where the pointer

falls on the scale. This should be done at eye level.

Tubular Spring Scale(How to Use)

Page 25: Lab Equipment Overview

Tubular Spring Scale (Example)

• What weight (in newtons) is being displayed by the spring scale?

Since each graduated marking is equivalent to 0.5 N, the weight

being displayed by the spring scale is 6 N.

Page 26: Lab Equipment Overview

Thermometer(Overview)

• Used to measure temperature• Units of measure: Celsius (0C),

Fahrenheit (0F), Kelvin (K) • Relies on the expansion and

contraction property of fluids – this is why the fluid (alcohol) rises as the temperature goes up and falls as the temperature goes down

• Celsius and Fahrenheit scales meet at – 40 degrees

• Relationships between scales:– 0C = 5/9 (0F – 32)– 0F = 9/5 0C + 32– K = 0C +273

Page 27: Lab Equipment Overview

1. Determine what scale you will be using (Fahrenheit or Celsius).

2. Similar to when using a graduated cylinder or spring scale, determine the value of each graduated marking, or line, found on the thermometer – knowing this will help you determine the temperature.

3. Set up a ring stand with clamp on a flat surface.4. Carefully tighten the thermometer into the clamp.5. Place the object/substance to be measured on the

base of the ring stand.6. Lower the thermometer into the object/substance. Be

sure to not allow the bulb of the thermometer to sit on or touch the container holding the object/substance.

7. Measure the temperature of the object/substance by reading where the top of the red liquid (alcohol) aligns with the appropriate scale. This should be done at eye level.

Thermometer(How to Use)

Page 28: Lab Equipment Overview

Thermometer (Example)

• What is the temperature (in degrees Fahrenheit and Celsius) being displayed by the thermometer below?

74 0F

23 0C

0F 0C