Required Practical 4 ✔️(Density)

Question 1

Aim of the experiment?

Answer 1

Determine the densities of regular and irregular solid objects and liquids - by determining the dimensions of regular objects and by a displacement technique for irregularly shaped objects

Question 2

What equipment is involved?

Answer 2

• various regular and irregular shaped objects
• suitable liquid
• 30 cm ruler
• digital balance
• variety of measuring cylinders
• ureka cup

Question 3

Method for caculating the density of regular objects - steps 1 and 2?

Answer 3

1) measure the length, height and width of the object - record your values to nearest mm

2) caculate the volume - length x height x width

Question 4

Method for caculating the density of regular objects - steps 3 and 4?

Answer 4

3) measure the mass of the object - use the mass balance - reset the balance with nothing on the scales - to reduce zero errors

4) caculate density by dividing mass from volume

Question 5

Method for caculating the density of irregular shaped objects - steps 1 and 2?

Answer 5

1) fill the eureka cup with water and align a measuring beaker under spout - make sure level of water lies just below the spout

2) place the irregular shaped object into the cup slowly - do not drop it or cause it to splash

Question 6

Method for caculating the density of irregular shaped objects - steps 3?

Answer 6

3) Collect the displaced water from the measuring cylinder - measure the volume of water displaced - use the mass obtained by the mass balance and work out density

Question 7

Method for caculating density of liquid steps 1 to 3?

Answer 7

1) measure the mass of an empty measuring beaker - use the mass-balance

2) pour 100cm of liquid into the beaker

3) measure the combined mass of the beaker and liquid

Question 8

Method for caculating density of liquid steps 4 and 5?

Answer 8

4) caculate the liquids mass - by subtracting the mass of the beaker from the mass of the combined beaker and liquid

5) caculate denisity of the liquid - using density equation

Question 9

Safety precautions?

Answer 9

• take care handling glass equipment
• clean any spillages of water

Question 10

Why do we reset the mass balacne when we place the object on it?

Answer 10

To reduce zero error