CO2 & CH4 as Greenhouse Gases (AQA GCSE Chemistry: Combined Science)

Methane gas is a gas present in the atmosphere and which most scientists think is a cause of global climate change.

The levels of methane in the atmosphere measured from 1995 to 2015 are shown in Figure 1.

Figure 1

Calculate the increase in methane between 2000 and 2012.

How did the amount of methane in the atmosphere change between 2003 and 2005?

Tick (✔) one box. 

Name two human activities that increase the amount of methane in the atmosphere.

The greenhouse effect allows the Earth to stay warm enough to support life. 

Which explanation correctly describes a part of the greenhouse effect?

Global climate change has serious consequences on the environment. 

Which of the following shows an incorrect effect of global climate change?

This question is based on the temperature of the Earth’s atmosphere.

Give three reasons why producing models for future climate change is difficult.

Describe the way in which carbon dioxide helps to maintain temperatures on the Earth.

Carbon dioxide is a greenhouse gas.

Name the other two greenhouse gases.

This question is about carbon dioxide in the atmosphere.

Give three ways in which carbon dioxide is released into the atmosphere by industrial and human activity.

Give three ways in which carbon dioxide is released into the atmosphere by geological activity on carbonate rocks.

Explain how the greenhouse gases can increase the temperature of the Earth.

Give three environmental effects of global climate change.

This question is about carbon footprints.

Explain what the term ‘carbon footprint’ means.

Describe ways in which the carbon footprint can be reduced.

Human activities are contributing to the increase of greenhouse gases in the atmosphere. 

Which two human activities contribute to the release of methane?

Burning fuels, such as petrol in cars, contributes large amounts of carbon dioxide to the atmosphere. 

What could be done to reduce this cause of pollution?

This question is about climate change.

Changes in the global mean air temperature and global mean sea level from 1992 to 2016 are shown in Figure 1.

Figure 1

Use Figure 1 to calculate the mean annual increase in sea level between 1992 and 2016.

Mean yearly increase in sea level = ____________________ mm / year

Most scientists now agree that carbon dioxide and methane are a cause of global climate change.

The amount of both of these gases in the atmosphere from 1992 to 2016 is shown in Figure 2.

Figure 2

Describe and explain the changes that have occurred between 1992 and 2016. 

You should refer to Figures 1 and 2 in your answer.

The data used to prepare figures 1 and 2 was collected by a single scientific group.

Give two reasons why more evidence should be collected to support any conclusions made by the scientific group.

This question is about the atmosphere.

The planet Saturn has many moons, including one named Titan. 

Titan's atmosphere is warmer than other moons because it contains methane, a greenhouse gas. 

Explain how methane keeps Titan warmer than other moons.

In addition to methane, other gases are found in the atmosphere of Titan.

These gases and their percentages are shown in Table 1. 

Table 1 

Explain why life could not have evolved in the same way it is thought to have evolved on Earth. 

Methane can also be used as a fuel and undergo combustion to produce carbon dioxide and water. 

The equation for this reaction can be shown as:

 Table 1

Use the bond energies in Table 1 to calculate the energy change for the reaction. 

Explain, in terms of bond making and breaking, why this is an exothermic reaction. 

This question is about global climate change. 

Figure 1 shows how the mean global air temperature has changed from 1860 to 2000.

Figure 1

Describe the main trend shown above and explain how human activities have contributed to it. 

Explain the effects of global climate change on the environment, humans and wildlife.

Describe how greenhouse gases help maintain temperatures on Earth. 

An alternative to using fuels obtained from crude oil, such as diesel oil (also known as fossil diesel) is to use biodiesel.

Biodiesel can be made from many vegetable oils. 

Biodiesel’s contribution to global warming is considered to be much less than that of fossil diesel.

Explain why.

Human activity is affecting the composition of the atmosphere. 

Suggest one reason how each of the following factors affects the level of carbon dioxide in the atmosphere. 

Increased energy consumption: ____________________________________________________________ 

Deforestation: ____________________________________________________________

A student says:

'If the amount of methane in the atmosphere continues to increase, it will lead to a drop in global food production in the future.'

Explain why the student could be right. 

Explain how an increasing population increases the carbon dioxide level in the atmosphere. 

Suggest two reasons why it is difficult to produce models for future climate change.