Nuclear fusion

Scientists have used lasers to start a nuclear fusion reaction.

The scientists used the lasers to heat a small amount of an isotope of hydrogen.

Describe what is meant by ‘isotopes’ of an element.

Explain how nuclear fusion releases energy.

The fusion reaction releases large amounts of energy.

The fusion reaction takes place in a reactor.

Explain why the walls of the reactor should be made from a material with a very high specific heat capacity.

Nuclear fusion is safer than nuclear fission.

Nuclear fission can lead to an uncontrolled chain reaction.

Give one consequence of an uncontrolled chain reaction.

Some isotopes emit nuclear radiation.

Carbon-12 and carbon-14 are both isotopes of carbon.

Complete the sentences.

Choose answers from the box.

The nucleus of a carbon-12 atom and the nucleus of a carbon-14 atom have the

same number of.

The nucleus of a carbon-12 atom and the nucleus of a carbon-14 atom have a

different number of.

Different radioactive isotopes have different half-lives.

What does ‘half-life’ mean?

Tick (✓) one box.

Table 2 shows the half-life of some different isotopes of carbon.

Which isotope is the least stable?

Tick (✓) one box.

Workers in nuclear power stations must be aware of nuclear irradiation and radioactive contamination.

Draw one line from each term to an example of the term.

Why are workers required to walk across a sticky floor before leaving the nuclear power station?

Tick (✓) one box.

The places where people work and live contribute to the nuclear radiation they are exposed to.

Table 3 shows the mean daily dose of radiation caused by two different jobs.

Calculate the number of days a nuclear power station worker must work before receiving the same dose that an aeroplane pilot receives in one day.

The process of nuclear fission takes place in nuclear power stations.

The process of nuclear fusion takes place in the Sun.

Draw one line from each process to its fuel.

Energy from the Sun is released by nuclear fusion.

Complete the sentences.

Nuclear fusion of deuterium is difficult to achieve on Earth because of the high temperature needed.

Electricity is used to increase the temperature of 4.0 g of deuterium by 50 000 000 °C.

specific heat capacity of deuterium = 5200 J/kg °C

Calculate the energy needed to increase the temperature of the deuterium by 50 000 000 °C.

Use the Physics Equations Sheet.

The idea of obtaining power from nuclear fusion was investigated using models.

The models were tested before starting to build the first commercial nuclear fusion power station.

Suggest two reasons why models were tested.

Generating electricity using nuclear fusion will have fewer environmental effects than generating electricity using fossil fuels.

Explain one environmental effect of generating electricity using fossil fuels.

Energy from the Sun is released by nuclear fusion.

Complete the sentences.

Nuclear fusion of deuterium is difficult to achieve on Earth because of the high temperature needed. Electricity is used to increase the temperature of 4.0 g of deuterium by 50 000 000 °C. specific heat capacity of deuterium = 5200 J/kg °C Calculate the energy needed to increase the temperature of the deuterium by 50 000 000 °C. Use the Physics Equation Sheet.

The idea of obtaining power from nuclear fusion was investigated using models. The models were tested before starting to build the first commercial nuclear fusion power station. Suggest two reasons why models were tested.

Generating electricity using nuclear fusion will have fewer environmental effects than generating electricity using fossil fuels. Explain one environmental effect of generating electricity using fossil fuels.

Radioactive waste from nuclear power stations is a man-made source of background radiation.

Give one other man-made source of background radiation.

Nuclear power stations use the energy released by nuclear fission to generate electricity.

Give the name of one nuclear fuel.

Nuclear fission releases energy. Describe the process of nuclear fission inside a nuclear reactor.

A new type of power station is being developed that will generate electricity using nuclear fusion. Explain how the process of nuclear fusion leads to the release of energy.

Nuclear fusion power stations will produce radioactive waste. This waste will have a much shorter half-life than the radioactive waste from a nuclear fission power station. Explain the advantage of the radioactive waste having a shorter half-life.