Atomic Structure & Decay Equations (AQA A Level Physics): Exam Questions

An atom of ${}_{24}{}^{52}\mathrm{Cr}$ loses three electrons.

What is the specific charge of the ion?

A nucleus of ${}_{86}{}^{222}\mathrm{Rn}$ undergoes radioactive decay so that the decay product is ${}_{83}{}^{214}\mathrm{Bi}$ .

What combination of radioactive emissions could have occurred?

For the following decay equation, identify the type of decay and particle X.

 ${}_6{}^{11}\mathrm{C}\to {}_5{}^{11}\mathrm{B}$ + X + Y

What is the ratio of the specific charge of a proton compared to the specific charge of an alpha particle?

A radioactive nucleus absorbs a neutron, causing it to emit an α particle, and two β-minus particles. At each stage gamma radiation is also released.

What will be final nuclide be?

Astatine is a radioactive substance; it has a nucleon number of 218 and a proton number of 85. When it decays, it forms a polonium nucleus, emitting a β⁻ particle and an α-particle.

What are the nucleon number and the proton number of the polonium nucleus?

An atom of ${}_9{}^{19}\mathrm{F}$ gains 2 electrons.

What is the specific charge of the ion?

Antimatter is a particle that is an antiparticle to the corresponding particle. A positron is the antiparticle of an electron.

What is the difference between a positron and an electron?

An unstable nucleus decays by emitting an alpha (α) particle.

The new nucleus, and any subsequent nuclei that form, are unstable and may emit either an α or β⁻ particle. This process continues until an isotope of the original nucleus is formed.

Including the initial alpha emission, what is the minimum number of decays that could occur?

Two gamma photons are produced when an electron and a positron annihilate each other.

What is the minimum frequency of the gamma radiation that could be produced?

Which nuclear change results in the nucleus with the greatest specific charge?

A particular nucleus ${}_{\mathrm{Z}}{}^{\mathrm{A}}\mathrm{X}$ decays to form the nucleus ${}_{\mathrm{z}}{}^{\mathrm{a}}\mathrm{Y}$.

The nucleus ${}_{\mathrm{z}}{}^{\mathrm{a}}\mathrm{Y}$ can decay in one of two possible ways to form an isotope of Thallium (Tl) or Polonium (Po).

Which isotope could not be ${}_{\mathrm{Z}}{}^{\mathrm{A}}\mathrm{X}$?

What is the value of $\frac{specificchargeof{}_3{}^7\mathrm{Li}nucleus}{specificchargeof{}_8{}^{16}{\mathrm{O}}^{2+}ion}$?

A sample of radioactive material contains radium ${}_{88}{}^{221}Ra$,  which decays by α-decay to form radon, ${}_{86}{}^{217}Rn$ .

What percentage of the mass of the sample would be made up from radium, after half the nuclei had decayed?

The decay series of ${}_{90}{}^{232}\mathrm{Th}$ shows the possible nuclei that can form from alpha and beta emissions.

How many possible routes are available for ${}_{90}{}^{232}\mathrm{Th}$ to decay to a stable nucleus of ${}_{82}{}^{208}\mathrm{Pb}$?

Radioactive isotopes are used in medical imaging.

Two isotopes of iodine,  and , are used by radiographers to give to patients in the form of iodide before taking scans.

The incomplete decay equations for these isotopes are:

1.   ${}_{53}{}^{123}\mathrm{I}+...\to {}_{52}{}^{123}\mathrm{Te}+...$

2.   ${}_{53}{}^{131}\mathrm{I}\to {}_{54}{}^{131}\mathrm{Xe}+...+...$

Which statement gives the correct difference between these two decays?

A particular isotope decays through a series of alpha and beta emissions until a stable nucleus of ${}_{82}{}^{206}\mathrm{Pb}$ forms.

Which row correctly describes the nuclides labelled 1, 2 and 3?

The graph shows how the neutron-proton ratio of stable nuclei changes as proton number increases.

For increasing proton number, which of the following changes are correct?

1. the charge-mass ratio increases

2. the charge-mass ratio decreases

3. the likelihood of α-decay increases

4. the likelihood of β-plus decay increases

5. protons outnumber neutrons in large nuclei, with a rapidly increasing ratio

Nuclear power stations use a fission reactor to create a nuclear reaction. A nucleus absorbs one neutron, leading to a reaction where more than one neutron is released. These neutrons in turn will set off more reactions.

This process is called a chain reaction.

Which one of these decay processes would be suitable to create a chain reaction?

Following the development of the atomic bomb, scientists discovered that they could create elements heavier than uranium by bombarding nuclei with neutrons. These reactions, where smaller nuclei are combined to form a heavier nucleus are called fusion reactions.

Fusion reactions are balanced in exactly the same way as radioactive decay equations.

What are the missing products of these fusion reactions?

Radioactive sources are used in smoke detectors. Nuclides emitting α-particles are used because α-particles have low penetrating power.

Which of these nuclides is the most likely to be a good source of α-radiation?