Req Prac 4 Density

Question 1

Part 1: calculating the density of a regularly shaped object

Question 2

Outline the basic steps of the practical

Answer 2

1. Measure the dimensions of the regular shape and calculate the volume
2. Measure the mass of the shape using a calibrated balance
3. Calculate density from the mass and volume

Question 3

Give the formula for the volume of a prism

Answer 3

Volume = area of face x height

Question 4

What equation is used to calculate volume of a rectangular prism ?

Answer 4

Volume = length x width x height

Question 5

What equation is used to calculate density?

Answer 5

Density = mass / volume

Question 6

What unit is ised for density?

Answer 6

kg/m^3

Question 7

What piece of equipment is used to measure the object’s mass? What must you do before using it ?

Answer 7

A digital balance, which should be zeroed before placing the object on it to avoid a zero error

Question 8

How do you convert from g/cm^3 to kg/m^3

Answer 8

Multiply the value by 1000

Question 9

Part 2: calculating the density of a irregulalry shaped object

Question 10

2. Outline the basic steps of the practical

Answer 10

1. Measure the mass of the irregular shape
2. Fill a displacement can with water and submerge the object
3. Record the volume of water that has been displaced
4. Calculate the density from the mass and volume

Question 11

2. What should you place under the can spout to collect the water ?

Answer 11

A measuring beaker

Question 12

2. Explain how you should fill the displacement can to get the most accurate results

Answer 12

Fill the can until water starts to drip out of the spout and into the beaker . Wait until the dripping just stops before submerging the object

Question 13

Part 3: calculating the density of a liquid

Question 14

3. Outline the basic steps of the practical

Answer 14

1. Measure the mass of the empty measuring cylinder
2. Pour around 100cm^3 of liquid into the cylinder and record the volume
3. Measure the mass of the cylinder with liquid in, and subtract the cylinder’s mass to calculate the mass of liquid.
4. Calculate density from mass and volume

Question 15

3. How does the density of solids and liquids compare?

Answer 15

In general, solids are more dense than liquids since their particles are more tightly packed together meaning there is more mass per unit volume