Atmospheric pollutants

Photosynthesis produces glucose.

Name the other product of photosynthesis.

Do not refer to glucose in your answer.

A student investigated the effect of light intensity on the rate of photosynthesis in two species of aquatic plant.

Figure 4 shows the apparatus used.

This is the method used.

1. Place species A in water in a test tube.

2. Leave the test tube containing species A in a dark room for 10 minutes.

3. Put the test tube containing species A 20 cm away from the lamp.

4. Record the number of bubbles produced by species A in 5 minutes.

5. Repeat steps 2 to 4 at different distances from the lamp.

6. Repeat steps 1 to 5 using species B.

What was the independent variable in the investigation?

Tick () one box.

Light intensity

Size of each plant

Volume of water

The student collected valid results.

Figure 5 shows the results.

What was the number of bubbles produced by species B at 20 cm?

What distance between the lamp and test tube would cause the same number of bubbles in both species?

Use Figure 5.

As the distance between the lamp and the plant increases, the light intensity decreases.

The student concluded:

‘Species A had a greater rate of photosynthesis at low light intensity than species B.’

What evidence from Figure 5 supports the student’s conclusion?

Tick () one box.

Species A produced more bubbles than species B at 60 cm.

Species A produced 46 bubbles at 20 cm and 34 bubbles at 60 cm.

Species A produced fewer bubbles than species B at 20 cm.

Global dimming decreases the sunlight reaching the plants on the Earth’s surface.

Global dimming is caused by particulates in the atmosphere.

Which substance is a particulate emitted from diesel engines?

Tick () one box.

Carbon

Carbon dioxide

Carbon monoxide

Carbon monoxide is an atmospheric pollutant.

How is carbon monoxide formed?

Tick (✓) one box.

Incomplete combustion of hydrocarbons

Photosynthesis by plants

Purification of water

Carbon monoxide changes the amount of oxygen that blood can transport.

Which part of the blood transports oxygen?

Figure 1 shows how the percentage of carbon monoxide in air affects the concentration of oxygen in blood.

When the percentage of carbon monoxide in air is 40% the concentration of oxygen in blood is 64 arbitrary units.

Complete Figure 1 to show the result for 40% carbon monoxide in air.

The percentage of carbon monoxide in air changes from 0% to 80%.

Determine the change in the concentration of oxygen in blood.

Use Figure 1.

_ Change = _________________ arbitrary units

Describe how increasing the percentage of carbon monoxide in air affects the concentration of oxygen in blood.

Use Figure 1.

Breathing in carbon monoxide can cause carbon monoxide poisoning.

Which of the following is a symptom of carbon monoxide poisoning?

Tick (✓) one box.

Burns on the skin

Faster heart rate

High temperature

Carbon monoxide can build up in a room.

The risk of carbon monoxide poisoning can be reduced by opening windows in the room.

Suggest how opening windows reduces the risk of carbon monoxide poisoning.

Two students analysed water from four rivers.

Each student measured the pH of the river water using a different method.

Table 5 shows the results.

Suggest what was used to measure the pH in each method.

Why is it not valid to calculate a mean of the two pH values for each river?

Tick (✓) one box.

A mean cannot be calculated from only two values.

Each method gives values to a different resolution.

The mean should be calculated for each method using all four samples.

Which river is most likely to be in an area with a high concentration of sulfur dioxide in the air?

Use Table 5.

Tick (✓) one box.

W X Y Z

Explain your answer to Question 08.4.

Describe a method to determine the mass of dissolved solids in 50 cm³ of river water.

Two students analysed water from four rivers.

Each student measured the pH of the river water using a different method.

Table 1 shows the results.

Suggest what was used to measure the pH in each method.

Why is it not valid to calculate a mean of the two pH values for each river?

Tick (✓) one box.

A mean cannot be calculated from only two values.

Each method gives values to a different resolution.

The mean should be calculated for each method using all four samples.

Which river is most likely to be in an area with a high concentration of sulfur dioxide in the air?

Use Table 1.

Tick (✓) one box.

W X Y Z

Explain your answer to Question 01.4.

Describe a method to determine the mass of dissolved solids in 50 cm³ of river water.

Carbon monoxide is an atmospheric pollutant.

Carbon monoxide can have dangerous effects on the human body.

Describe how carbon monoxide is formed from hydrocarbon fuels.

Red blood cells contain haemoglobin.

Scientists investigated the effect of breathing in air containing different concentrations of carbon monoxide.

The scientists measured the percentage of haemoglobin molecules attached to oxygen at different concentrations of oxygen in the blood.

The air breathed contained:

no carbon monoxide

a low concentration of carbon monoxide.

Figure 5 shows the results.

A person: breathes in air containing no carbon monoxide

has a concentration of oxygen in the blood of 90 arbitrary units.

What percentage of haemoglobin molecules are attached to oxygen?

Use Figure 5.

The scientists repeated the investigation with air containing a higher concentration of carbon monoxide.

Table 3 shows the results.

Complete Figure 5.

You should:

plot the data from Table 3

draw a line of best fit.

A person breathes in air containing a low concentration of carbon monoxide.

Suggest two symptoms the person might show.

Explain why a high concentration of carbon monoxide in the air causes a person to become seriously ill.

This question is about the blood and the circulatory system.

Figure 12 shows a human heart.

Draw one arrow on Figure 12 to show the movement of the blood between the left atrium and the left ventricle.

Which blood vessel carries blood from the lungs into the heart?

Tick (✓) one box.

A B C D

Which blood vessel is the aorta?

Tick (✓) one box.

A B C D

What structures prevent blood flowing in the wrong direction through the heart?

Heart muscle cells obtain oxygen from the blood.

Which blood vessels exchange oxygen with heart muscle cells?

Tick (✓) one box.

Arteries

Capillaries

Veins

Heart rate is controlled by a group of cells called the pacemaker.

Where is the pacemaker in the heart?

Tick (✓) one box.

Left atrium

Left ventricle

Right atrium

Right ventricle

Carbon monoxide is a toxic gas.

Explain why an increase of carbon monoxide in the air increases heart rate.

A person was exposed to carbon monoxide in the air for 1 hour.

During the hour the person’s heart rate increased from 80 beats per minute to 130 beats per minute.

Calculate the percentage increase in heart rate.

Use the equation:

This question is about the blood and the circulatory system.

Figure 1 shows a human heart.

Draw one arrow on Figure 1 to show the movement of the blood between the left atrium and the left ventricle.

Which blood vessel carries blood from the lungs into the heart?

Tick (✓) one box.

A B C D

Which blood vessel is the aorta?

Tick (✓) one box.

A B C D

What structures prevent blood flowing in the wrong direction through the heart?

Heart muscle cells obtain oxygen from the blood.

Which blood vessels exchange oxygen with heart muscle cells?

Tick (✓) one box.

Arteries

Capillaries

Veins

Heart rate is controlled by a group of cells called the pacemaker.

Where is the pacemaker in the heart?

Tick (✓) one box.

Left atrium

Left ventricle

Right atrium

Right ventricle

Carbon monoxide is a toxic gas.

Explain why an increase of carbon monoxide in the air increases heart rate.

A person was exposed to carbon monoxide in the air for 1 hour.

During the hour the person’s heart rate increased from 80 beats per minute to 130 beats per minute.

Calculate the percentage increase in heart rate.

Use the equation:

Pollutants in the atmosphere can be harmful to the environment and to human health.

Four pollutants in the atmosphere are:

How is carbon monoxide produced?

Tick (✓) one box.

By carbon dioxide dissolving in water

From the incomplete combustion of hydrocarbon fuels

When carbonates form sedimentary rocks

What is formed when sulfur dioxide dissolves in moisture in the air?

Tick (✓) one box.

Acid rain

Methane

Ozone

Give one way that oxides of nitrogen can be harmful to human health.

Particulates are classified into different groups depending on the diameter of the particulate.

Table 1 shows information about the different groups.

Figure 7 shows a soot particle viewed using an electron microscope.

The diameter of the soot particle in Figure 7 is 1.5 micrometres.

Which particulate group does the soot particle belong to?

Use Table 1.

Tick (✓) one box.

PM₁₀

Why is an electron microscope and not a light microscope used to view the soot particle?

Figure 8 shows the emissions of particulates from two different sources in 1990 and in 2020.

Determine the difference between the emission of particulates from industrial processes and the emission of particulates from road transport in 1990.

Use Figure 8.

Emission of particulates from industrial processes = ___________ millions of kilograms

Emission of particulates from road transport = ___________ millions of kilograms

Difference in emissions of particulates in 1990 = ___________ millions of kilograms

Give three conclusions from Figure 8.

Pollutants in the atmosphere can be harmful to the environment and to human health.

Four pollutants in the atmosphere are:

Describe how carbon monoxide is produced from hydrocarbon fuels.

Describe one harmful effect of oxides of nitrogen.

Figure 7 shows the emissions of three atmospheric pollutants from 1970 to 2019.

Determine the percentage change in emission of oxides of nitrogen from 1970 to 2019.

Give your answer to 2 significant figures.

Compare the changes in the emission of atmospheric pollutants from 1970 to 2019.

You should refer to:

Use Figure 7.

Suggest one reason for the change in the emission of atmospheric pollutants shown in Figure 7.

Particulates are classified into different groups depending on diameter of the particulate.

Table 4 shows information about the different groups.

A soot particle was viewed using a microscope.

The magnification used was × 5000.

The diameter of the image of the soot particle was 7.5 mm.

Determine the particulate group of the soot particle.

1 mm = 1000 micrometres

Use Table 4.

Real diameter of soot particle = ____________________ micrometres

Particulate group.

Tick (✓) one box.

PM PM PM 10 2.5 0.1

Particulates in the air can be breathed in.

The body’s defences prevent particulates larger than 10 micrometres getting into the lungs.

Describe how the body prevents the particulates reaching the lungs and removes the particulates from the airways.

Sewers are often blocked by ‘fatbergs’.

Fatbergs are made of very large lumps of fat and other solids.

The fat and solids come from waste being washed down drains and flushed down toilets.

Figure 11 shows a person holding a small fatberg.

The chemical composition of fatbergs can be tested.

Describe how a sample from a fatberg could be tested for fat and for protein.

Positive result for fat

Positive result for protein

Some fats in fatbergs come from undigested food in faeces.

Most fat that humans eat is digested.

Give the two products of fat digestion.

It may be possible to use fatbergs as a fuel in power stations.

Burning 1.0 kg of fatbergs transfers 40 MJ of energy.

A power station could burn 1250 kg of fatbergs each hour.

Calculate the energy output from the power station in 1 year.

1 year = 8760 hours

Energy output in 1 year = MJ

Evaluate burning fatbergs in power stations compared with burning coal in power stations.

Sewers are often blocked by ‘fatbergs’.

Fatbergs are made of very large lumps of fat and other solids.

The fat and solids come from waste being washed down drains and flushed down toilets.

Figure 2 shows a person holding a small fatberg.

The chemical composition of fatbergs can be tested.

Describe how a sample from a fatberg could be tested for fat and for protein.

Positive result for fat

Positive result for protein

Some fats in fatbergs come from undigested food in faeces.

Most fat that humans eat is digested.

Give the two products of fat digestion.

It may be possible to use fatbergs as a fuel in power stations.

Burning 1.0 kg of fatbergs transfers 40 MJ of energy.

A power station could burn 1250 kg of fatbergs each hour.

Calculate the energy output from the power station in 1 year.

1 year = 8760 hours

Evaluate burning fatbergs in power stations compared with burning coal in power stations.