Atomic Structure & Radioactivity Quiz

Question 1

What are the three subatomic particles that make up an atom?

Accepted Answer

Protons, neutrons, and electrons

Answer

Neutrons, electrons, and photons

Answer

Protons, quarks, and electrons

Answer

Nucleons, electrons, and ions

Question 2

What is the atomic number of an element?

Accepted Answer

The number of protons in the nucleus

Answer

The total number of protons and neutrons

Answer

The number of electrons in the outer shell

Answer

The mass of the atom

Question 3

What are isotopes?

Accepted Answer

Atoms of the same element with different numbers of neutrons

Answer

Atoms of different elements with the same mass number

Answer

Ions with different charges

Answer

Radioactive forms of any element

Question 4

What is the plum pudding model of the atom?

Accepted Answer

An early model by J.J. Thomson showing electrons embedded in a diffuse sphere of positive charge

Answer

A model where electrons orbit the nucleus in shells

Answer

A model showing a nucleus surrounded by empty space

Answer

A model with electrons in fixed energy levels

Question 5

What did Rutherford's gold foil experiment discover?

Accepted Answer

That atoms have a small, dense, positively charged nucleus with mostly empty space around it

Answer

That electrons orbit the nucleus

Answer

That atoms are indivisible

Answer

That neutrons exist in the nucleus

Question 6

What is radioactive decay?

Accepted Answer

The spontaneous emission of radiation from an unstable atomic nucleus as it becomes more stable

Answer

The chemical reaction of a radioactive substance with oxygen

Answer

The breakdown of a compound at high temperature

Answer

The loss of electrons from a metal in solution

Question 7

What is an alpha (α) particle?

Accepted Answer

A helium nucleus — 2 protons and 2 neutrons

Answer

A high-energy electron

Answer

A high-energy electromagnetic wave

Answer

A neutron released from the nucleus

Question 8

What is a beta (β) particle?

Accepted Answer

A fast-moving electron emitted from the nucleus when a neutron converts to a proton

Answer

A helium nucleus

Answer

A high-energy photon

Answer

A neutron ejected from the nucleus

Question 9

What is gamma (γ) radiation?

Accepted Answer

High-energy electromagnetic radiation emitted from the nucleus after alpha or beta decay

Answer

A particle with high mass and charge

Answer

Slow-moving electrons

Answer

A stream of protons

Question 10

What is half-life?

Accepted Answer

The time for half the radioactive atoms in a sample to decay

Answer

The time for all atoms in a sample to decay

Answer

The energy released when half the atoms decay

Answer

The time for a sample to lose half its mass

Question 11

A radioactive sample has a half-life of 10 years. After 30 years, what fraction of the original sample remains?

Accepted Answer

1/8

Answer

1/2

Answer

1/4

Answer

1/6

Question 12

What is nuclear fission?

Accepted Answer

A large nucleus splitting into smaller nuclei, releasing a huge amount of energy

Answer

Small nuclei combining to form a larger one

Answer

Radioactive decay producing alpha particles

Answer

The orbiting of electrons changing energy levels

Question 13

What is nuclear fusion?

Accepted Answer

The combining of small nuclei to form a larger one, releasing enormous energy

Answer

The splitting of a large nucleus

Answer

The decay of a radioactive nucleus

Answer

The absorption of a neutron by a nucleus

Question 14

Which type of radiation is the most penetrating?

Accepted Answer

Gamma

Answer

Alpha

Answer

Beta

Answer

All are equally penetrating

Question 15

What is ionising radiation?

Accepted Answer

Radiation with enough energy to remove electrons from atoms, creating ions

Answer

Radiation that only travels through space

Answer

Radiation that cannot penetrate matter

Answer

Sound waves at very high frequencies

Question 16

What is carbon-14 dating used for?

Accepted Answer

Determining the age of organic materials up to about 50,000 years old using the known half-life of carbon-14

Answer

Dating rocks billions of years old

Answer

Tracking nuclear reactor fuel

Answer

Measuring uranium content in minerals

Question 17

In which direction do alpha particles, beta particles, and gamma rays deflect in a magnetic field?

Accepted Answer

Alpha and beta deflect in opposite directions; gamma is undeflected

Answer

All deflect in the same direction

Answer

Only gamma deflects; alpha and beta do not

Answer

All three deflect in the same direction but different amounts

Question 18

What medical application uses gamma radiation?

Accepted Answer

Treating cancer tumours with targeted gamma rays (radiotherapy)

Answer

X-ray imaging

Answer

Ultrasound scanning

Answer

Blood pressure monitoring

Question 19

What is background radiation?

Accepted Answer

Low-level radiation that is always present in the environment from natural and artificial sources

Answer

Radiation from nuclear power plants only

Answer

Radiation that exists only in space

Answer

Radiation emitted by all electronic devices

Question 20

What change occurs in the nucleus during alpha decay?

Accepted Answer

Atomic number decreases by 2; mass number decreases by 4

Answer

Atomic number increases by 1; mass number unchanged

Answer

Atomic number unchanged; mass number decreases by 1

Answer

Atomic number increases by 2; mass number increases by 4