The structure of an atom

Which statement about electrons in atoms is correct ?

A Electrons gain energy as they absorb electromagnetic waves.

B Electrons have a positive charge.

C Electrons lose energy by emitting alpha particles.

D Electrons rise to higher energy levels as they emit electromagnetic waves.

There are different isotopes of the element carbon.

When carbon-14 decays into nitrogen-14, it emits beta radiation.

Complete the equation for the decay of carbon-14.

Carbon-14 has a half-life of 5700 years.

Explain what half-life means.

Alpha particles, beta particles, and gamma rays can penetrate different types and thicknesses of material.

Draw one line from each type of radiation to the type and maximum thickness of material radiation is able to penetrate.

Type of radiation
Type and maximum thickness of material

Security markings can be written on items you own. These are written using a fluorescent ink which is only visible under an ultraviolet lamp.

The diagram shows a security code ABCXYZ written on a black surface.

Particles inside the atoms in the ink absorb energy from ultraviolet radiation.

The same particles inside the atoms in the ink re-emit the energy as waves in the visible light region of the electromagnetic spectrum.

Which particles inside the atom absorb ultraviolet radiation and emit visible light?

Describe what happens to these particles when they absorb ultraviolet radiation.

Electromagnetic waves with short wavelengths can cause ionisation when absorbed by these particles inside the atom.

Describe the effect ionisation has on the atom.

Radio waves and microwaves are both electromagnetic waves.

Describe the difference in frequency between radio waves and microwaves.

Describe one use that radio waves and microwaves have in common.

An atom absorbs electromagnetic radiation.

What happens to some electrons in this atom?

A They form a neutron.

B They form a new element.

C They move from a high energy level to a lower energy level.

D They move from a low energy level to a higher energy level.

How much of the total mass of a hydrogen atom is made up by the nucleus?

A None of the mass

B Half of the mass

C Almost all of the mass

D All of the mass

This question is about radioactivity.

Which statements about the nucleus of an atom are correct? Tick (✓) two boxes.

The graph shows how the mass of a radioactive element changes with time.

Describe the trend shown by the graph.

This question is about two radioactive isotopes, X and Y.

Isotope X gives out gamma rays.

The charge on the nucleus of isotope X stays the same.

What happens to the mass number of the nucleus?

Isotope X is stored safely in a container.

Suggest a material for the container.

Describe how an object can be irradiated using isotope X.

Equal amounts of isotope Y are placed in a plastic box and in a cardboard box.

Table 11.1 gives information about both boxes.

Which box is best for storing isotope Y ?

Give one reason for your answer using the information in Table 11.1.

The plastic box does not let any of the radiation emitted by isotope Y pass through it.

Which type of radiation does isotope Y emit?

The graph shows how the quantity of isotope Y changes with time.

Complete Table 11.2 using the graph to help you.

Explain why the half-life of isotope Y is 5 days.

This is a model of energy levels inside a hydrogen atom.

Which electron movement, A, B, C or D, shows ionisation?

Carbon-12 is a stable isotope. Carbon-14 is an unstable radioactive isotope.

Describe what is meant by the term isotope.

This is the equation for the radioactive decay of carbon-14:

Which type of radiation is emitted by carbon-14?

Describe how the mass and charge of the nucleus changes when the carbon-14 decays.

Mass........

Charge........

Carbon-14 can be used to date ancient objects.

An ancient object is 17 100 years old. The half-life of carbon-14 is 5700 years.

For the ancient object, what is the ratio of the original amount of carbon-14 to the amount of carbon-14 left?

This question is about different types of radiation.

An isotope emits one type of radiation. It could be alpha, beta or gamma.

Describe how a teacher could show the type of radiation emitted using school equipment.

You may include a diagram in your answer.

Describe how these atoms can emit radiation.

What type of radiation is emitted?

Which of the following is not part of the atomic model?

A Almost all of an atom’s mass is contained in the nucleus.

B An atom’s nucleus contains positive neutrons.

C An atom’s nucleus is located in the centre of the atom.

D An atom’s nucleus is surrounded by electrons.

Atoms contain electrons. An atom can lose its outer electrons.

What is this process called?

A Friction

B Ionisation

C Radiation

D Radioactive decay

This is a model of energy levels inside an atom.

Which electron movement emits radiation with the highest energy?