Density

The photograph shows a ring made of gold.

(Source: ©Michael Burrell / Alamy Stock Photo)

A student wants to determine the volume of the ring.

The student measures the mass of the ring several times.

Describe how the student should use laboratory equipment to accurately measure the mass of the ring.

The table shows the student’s measurements of the mass of the ring.

One of the student’s measurements is an anomaly.

Draw a circle around the anomalous result in the table.

Calculate the mean mass of the gold ring.

The student is given a value for the density of gold.

Which of these formulae should be used to calculate the volume of the gold ring?

The student does not know if the ring is made of pure gold.

The student suggests that they could also measure the volume of the ring using a displacement method.

Discuss which method (calculation method or displacement method) will give the most accurate volume measurement.

A student plays a game using a single dice.

The student decides to determine the density of the dice by measuring its mass and volume.

Describe how the student could accurately measure the mass of the dice.

The dice is not a regular shape.

The student decides to measure the volume of the dice using a displacement method.

The student places the dice into a measuring cylinder containing water.

The diagram shows the water in the measuring cylinder before and after the dice is fully submerged.

The measuring cylinder gives volume in units of cm³.

Using the diagram, determine the volume of the dice.

The dice has a mass of 9.2 g.

Calculate the density of the dice using the formula

Give a suitable unit.

A student needs to determine the density of some small rocks that appear to all be made of the same material.

The student decides to measure the mass and the volume of each rock.

Describe a method the student could use to accurately determine the mass and the volume of each rock.

You may draw a diagram to help your answer.

The table shows the student’s results for three of the rocks.

State the formula linking density, mass and volume.

After looking at the data, the student concludes that one of the rocks may be made of a different material from the others.

Using the data from the table, justify the student’s conclusion.

The photograph shows an x-ray image of a person’s knee. The person has had part of their knee replaced.

X-rays are part of the electromagnetic spectrum.

All electromagnetic waves are transverse waves and transfer energy.

State another property that all electromagnetic waves have in common.

State a harmful effect of excessive exposure to x-rays.

Describe the difference between transverse waves and longitudinal waves.

You may draw a diagram to help your answer.

The diagram shows a part of the knee called the patella. The patella has been removed from a person’s knee.

The patella is a small, irregularly shaped bone that is denser than water.

Describe how to find the mass and the volume of the patella bone.

A scientist finds the volume and mass of a patella.

The mass of the patella is 17 g.

The volume of the patella is 13 cm³.

Calculate the density of the patella.

Give your answer to 2 significant figures.

density =_........ g / cm³

A student wants to determine the density of air using an irregularly‑shaped balloon made of metal foil.

The balloon has a label stating that the volume of the balloon when full is 490 cm³.

This is part of the student’s method.

Step 1 measure the mass of the empty balloon

Step 2 fill the balloon with air

Step 3 measure the mass of the full balloon

Step 4 subtract the mass of the empty balloon from the mass of the full balloon.

Name the equipment the student could use to measure the mass of the balloon.

Suggest how the student could improve the reliability of their data.

The table shows the student’s results.

Calculate the density of air to 2 significant figures.

Give the unit.

Describe how the volume of the balloon full of air could be measured using a large beaker and some water.

You may use a diagram to help your answer.

Hailstones are small pieces of ice that sometimes fall to the ground during storms.

Describe how to determine the density of a hailstone.

Assume that hailstones are spherical.

The mean volume of a hailstone is 1.1 cm³.

The mean mass of a hailstone is 0.94 g.

Calculate the mean density of a hailstone.

Give the unit.

Hailstones can be lifted to the top of clouds.

The diagram shows the movement of some hailstones in a cloud.

Suggest how hailstones are lifted to the top of the cloud by convection.

A student uses a balance to measure the mass of an object.

This is the student’s method.

● adjust the balance so that it displays a reading of zero

● place the object on the balance and record the reading

The student repeats this measurement several times.

What is improved by adjusting the balance to give a reading of zero before the object is placed on it?

What is improved by repeating the measurement?

The student measures the mass of the object using six different balances.

The table shows the student’s results.

Draw a circle around the anomalous reading in the table.

Calculate the mean mass of the object.

State what other measurement the student would need to make to determine the density of the object.

A student uses a bottle and a stopper to find the density of an unknown liquid.

The stopper fits tightly into the bottle and has a small diameter hole through it.

This is the student’s method.

use a balance to find the mass of the bottle and stopper completely fill the bottle with water insert the stopper and dry the outside of the bottle use the balance to find the mass of the full bottle and stopper

These are the student’s results.

mass of empty bottle and stopper = 63.4 g

mass of full bottle and stopper = 112.9 g

Use the student’s results to determine the volume of the water in the bottle.

Give your answer to three significant figures.

[density of water = 0.998 g/cm³]

volume =_........ ³

The student empties the bottle and then dries it.

He refills the bottle with the unknown liquid.

He measures the mass of the full bottle and stopper as 143.8 g.

Calculate the density of the unknown liquid.

Another student uses a measuring cylinder to find the volume of the unknown liquid.

Discuss the advantages and disadvantages of using each method to find the volume of the unknown liquid.

A student needs to identify a sample of an unknown liquid.

She decides to do this by finding the density of the liquid.

Describe how the student should measure the mass of the liquid.

Describe how the student should use a measuring cylinder to obtain an accurate measurement of the liquid’s volume.

The table gives the values of the densities for some liquids.

The student measures the mass of the sample of unknown liquid as 150 g and the volume as 163 cm³.

Deduce the name of the unknown liquid.

This question is about liquid nitrogen.

The diagram shows the arrangement of particles in solid nitrogen.

Draw the arrangement of particles in liquid nitrogen.

Describe the motion of the particles in liquid nitrogen.

A teacher uses this method to find the density of liquid nitrogen.

• measure the mass of a container

• pour liquid nitrogen into the container

• measure the total mass of the container and the liquid nitrogen

• read the volume of the liquid nitrogen from the scale on the side of the container

Give a safety precaution the teacher should take when pouring the liquid nitrogen.

State the name of the apparatus that the teacher should use to measure the mass of the container.

The table shows the teacher’s results.

Calculate the mass of liquid nitrogen in the container.

State the formula linking density, mass and volume.

Calculate the density of the liquid nitrogen.

Give a suitable unit.

Over time, the liquid nitrogen warms up and changes state from a liquid into a gas.

Describe the changes to the arrangement and motion of particles when the liquid nitrogen changes state.

The photograph shows a brass mass.

State the formula linking density, mass and volume.

The brass mass has a mass of 454 g.

The density of brass is 8.46 g/cm³.

Calculate the volume of the brass mass.

Give the unit.

The photograph shows a small glass ball used to investigate density and pressure.

The mass of the ball is 19 g.

The density of the ball is 2.3 g/cm³.

State the formula linking density, mass and volume.

Calculate the volume of the ball.

The ball is dropped into deep water and sinks to a depth of 560 cm.

State the formula linking pressure difference, height, density and gravitational field strength.

Calculate the increase in pressure at this depth.

[density of water = 1000 kg/m³]