Alpha, Beta, Gamma - exam practice

Which statement about alpha, beta and gamma radiation is correct?

A radioactive nucleus emits a β⁻ particle then an α particle and finally another β⁻ particle. The final nuclide is

The diagram shows an area of 0.10 m² normal to a line connecting it to a point source of

gamma radiation. The source emits photons uniformly in all directions.

The area and the source are separated by a distance of 2.0 m.

The source emits 5,000 gamma photons per second.

How many photons pass through the area every second?

When a small radioactive source is placed in a cloud chamber, straight tracks about 4 cm long are observed. The same source is placed 10 cm from a Geiger tube and a count rate is detected. When a sheet of aluminium 5 mm thick is placed between the source and the Geiger tube the count rate falls to the background count rate.

Which types of radiation are emitted by the source?

The first artificial radioactive substance was made by bombarding aluminium, with alpha particles. This produced an unstable isotope of phosphorus.

What was the by-product of this reaction?

Which statement about nuclei is correct?

An atomic nucleus emits a β-particle.

What change does this cause to the proton number and the nucleon number of the nucleus?

It was once thought that the mass of an atom is spread uniformly through the volume of the atom.

When α-particles are directed at a piece of gold foil, the results led scientists to believe instead that nearly all the mass of the gold atom is concentrated at a point inside the atom.

Which effect is possible onlyif nearly all the mass of the gold atom is concentrated at a point?

When α-particles are fired at a thin metal foil, most of the particles pass straight through but a few are deflected by a large angle.

Which change would increase the proportion of α-particles deflected by a large angle?