Atomic Structure & Radioactivity Quiz

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

1. Neutrons, electrons, and photons
2. Nucleons, electrons, and ions
3. Protons, neutrons, and electrons
4. Protons, quarks, and electrons

2. What is the atomic number of an element?

1. The mass of the atom
2. The number of electrons in the outer shell
3. The number of protons in the nucleus
4. The total number of protons and neutrons

3. What are isotopes?

1. Atoms of different elements with the same mass number
2. Atoms of the same element with different numbers of neutrons
3. Ions with different charges
4. Radioactive forms of any element

4. What is the plum pudding model of the atom?

1. A model showing a nucleus surrounded by empty space
2. A model where electrons orbit the nucleus in shells
3. A model with electrons in fixed energy levels
4. An early model by J.J. Thomson showing electrons embedded in a diffuse sphere of positive charge

5. What did Rutherford's gold foil experiment discover?

1. That atoms are indivisible
2. That atoms have a small, dense, positively charged nucleus with mostly empty space around it
3. That electrons orbit the nucleus
4. That neutrons exist in the nucleus

6. What is radioactive decay?

1. The breakdown of a compound at high temperature
2. The chemical reaction of a radioactive substance with oxygen
3. The loss of electrons from a metal in solution
4. The spontaneous emission of radiation from an unstable atomic nucleus as it becomes more stable

7. What is an alpha (α) particle?

1. A helium nucleus — 2 protons and 2 neutrons
2. A high-energy electromagnetic wave
3. A high-energy electron
4. A neutron released from the nucleus

8. What is a beta (β) particle?

1. A fast-moving electron emitted from the nucleus when a neutron converts to a proton
2. A helium nucleus
3. A high-energy photon
4. A neutron ejected from the nucleus

9. What is gamma (γ) radiation?

1. A particle with high mass and charge
2. A stream of protons
3. High-energy electromagnetic radiation emitted from the nucleus after alpha or beta decay
4. Slow-moving electrons

10. What is half-life?

1. The energy released when half the atoms decay
2. The time for a sample to lose half its mass
3. The time for all atoms in a sample to decay
4. The time for half the radioactive atoms in a sample to decay

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

1. 1/2
2. 1/4
3. 1/6
4. 1/8

12. What is nuclear fission?

1. A large nucleus splitting into smaller nuclei, releasing a huge amount of energy
2. Radioactive decay producing alpha particles
3. Small nuclei combining to form a larger one
4. The orbiting of electrons changing energy levels

13. What is nuclear fusion?

1. The absorption of a neutron by a nucleus
2. The combining of small nuclei to form a larger one, releasing enormous energy
3. The decay of a radioactive nucleus
4. The splitting of a large nucleus

14. Which type of radiation is the most penetrating?

1. All are equally penetrating
2. Alpha
3. Beta
4. Gamma

15. What is ionising radiation?

1. Radiation that cannot penetrate matter
2. Radiation that only travels through space
3. Radiation with enough energy to remove electrons from atoms, creating ions
4. Sound waves at very high frequencies

16. What is carbon-14 dating used for?

1. Dating rocks billions of years old
2. Determining the age of organic materials up to about 50,000 years old using the known half-life of carbon-14
3. Measuring uranium content in minerals
4. Tracking nuclear reactor fuel

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

1. All deflect in the same direction
2. All three deflect in the same direction but different amounts
3. Alpha and beta deflect in opposite directions; gamma is undeflected
4. Only gamma deflects; alpha and beta do not

18. What medical application uses gamma radiation?

1. Blood pressure monitoring
2. Treating cancer tumours with targeted gamma rays (radiotherapy)
3. Ultrasound scanning
4. X-ray imaging

19. What is background radiation?

1. Low-level radiation that is always present in the environment from natural and artificial sources
2. Radiation emitted by all electronic devices
3. Radiation from nuclear power plants only
4. Radiation that exists only in space

20. What change occurs in the nucleus during alpha decay?

1. Atomic number decreases by 2; mass number decreases by 4
2. Atomic number increases by 1; mass number unchanged
3. Atomic number increases by 2; mass number increases by 4
4. Atomic number unchanged; mass number decreases by 1