State the nuclear equation for the fusion reaction.

Nuclear fusion reactors are predicted to become an important source of electrical energy in the future. State two advantages of nuclear fusion over nuclear fission.

Suggest one reason why there is opposition to the increased use of nuclear fission reactors.

The half-life of ²³⁸U is $4.46\times {10}^9$ years. Calculate the mass of ²³⁸U that remains after $0.639 \mathrm{kg}$ has decayed for $2.23\times {10}^{10}$ years.

Compare and contrast fission and fusion in terms of binding energy and the types of nuclei involved.

Deduce the identity of X.

Outline why the reaction releases energy.

Determine the other product of the fission reaction of plutonium-239.

Compare and contrast the process of nuclear fusion with nuclear fission.

The daughter product, ⁸⁹Kr, has a half-life of 3.15 min.

Calculate the time required, in minutes, for the mass of ⁸⁹Kr to fall to 6.25 % of its initial value.

Outline why the reaction releases energy.

Explain why this fusion reaction releases energy by using section 36 of the data booklet.

Write the nuclear equation for this fission reaction.

The amount of ²²⁸Ac in a sample decreases to one eighth $\left(\frac{1}{8}\right)$ of its original value in about 18 hours due to β-decay. Estimate the half-life of ²²⁸Ac.

The critical mass for weapons-grade uranium can be as small as 15 kg. Outline what is meant by critical mass by referring to the equation in (a)(i).

Outline why this reaction results in a release of energy.

Beryllium-8 is a radioactive isotope with a half-life of 6.70 × 10⁻¹⁷ s.

Calculate the mass of beryllium-8 remaining after 2.01 × 10⁻¹⁶ s from a sample initially containing 4.00 g of beryllium-8.

Outline the concept of critical mass with respect to fission reactions.

Radioactive phosphorus, ³³P, has a half-life of 25.3 days.

(i) Calculate ³³P decay constant λ and state its unit. Use section 1 of the data booklet.

(ii) Determine the fraction of the ³³P sample remaining after 101.2 days.

Write the nuclear equation for this fission reaction.

Outline how the spectra of light from stars can be used to detect the presence of carbon.

One fusion reaction occurring in the sun is the fusion of deuterium, ${}_1^{2}H$, with tritium, ${}_1^{3}H$, to form helium, ${}_2^{4}He$. State a nuclear equation for this reaction.

⁹⁰Sr, a common product of fission, has a half-life of 28.8 years.

Determine the number of years for the activity of a sample of ⁹⁰Sr to fall to one eighth ($\frac{1}{8}$) of its initial value.

Outline the concept of critical mass with respect to fission reactions.

State one advantage of using fusion reactions rather than fission to generate electrical power.

Nuclear disasters release radioactive caesium into the atmosphere, which presents serious health risks.

Cs-137 has a half-life of 30 years.

Calculate the percentage of Cs-137 remaining in the atmosphere after 240 years.

Suggest two advantages that fusion has over fission.

(i) Explain why fusion, combining two smaller nuclei into a larger nucleus, releases vast amounts of energy. Use section 36 of the data booklet.

(ii) Outline one advantage of fusion as a source of energy.

The critical mass for weapons-grade uranium can be as small as 15 kg. Outline what is meant by critical mass by referring to the equation in (a)(i).

Determine the other product of the fission reaction of plutonium-239.

$${}_{94}^{239}\text{Pu + }{}_0^1\text{n}\to {}_{54}^{134}\text{Xe + }.................{\text{ + 3}}_0^1\text{n}$$

Outline one advantage of allowing all countries access to the technology to generate electricity by nuclear fission.

State the nuclear equation for the fusion reaction.

Deduce the nuclear equation for the decay of uranium-238 to thorium-234.

Dubnium-261 has a half-life of 27 seconds and rutherfordium-261 has a half-life of 81 seconds.

Estimate what fraction of the dubnium-261 isotope remains in the same amount of time that $\frac{3}{4}$ of rutherfordium-261 decays.

State one advantage of using fusion reactions rather than fission to generate electrical power.

Beryllium-8 is a radioactive isotope with a half-life of 6.70 × 10⁻¹⁷ s.

Calculate the mass of beryllium-8 remaining after 2.01 × 10⁻¹⁶ s from a sample initially containing 4.00 g of beryllium-8.

Deduce the nuclear equation for the decay of uranium-238 to thorium-234.

Explain how ²³⁵U fission results in a chain reaction, including the concept of critical mass.

Nuclear disasters release radioactive caesium into the atmosphere, which presents serious health risks.

Cs-137 has a half-life of 30 years.

Calculate the percentage of Cs-137 remaining in the atmosphere after 240 years.

The half-life of ²³⁸U is $4.46\times {10}^9$ years. Calculate the mass of ²³⁸U that remains after $0.639 \mathrm{kg}$ has decayed for $2.23\times {10}^{10}$ years.