Chemistry Test Nuclear Chemistry

Question 1

What particle is emitted during alpha decay?

Accepted Answer

Helium-4 nucleus (²₂He)

Answer

Alpha decay emits an alpha particle, which is identical to a helium-4 nucleus (2 protons and 2 neutrons, ²₄He).

Question 2

During beta-minus (β⁻) decay, which particle is emitted from the nucleus?

Accepted Answer

Electron

Answer

In beta-minus decay, a neutron converts to a proton and emits an electron (β⁻ particle) and an antineutrino.

Question 3

What is the half-life of a radioactive isotope?

Accepted Answer

Time for half the radioactive atoms to decay

Answer

The half-life is the time required for exactly half of the radioactive nuclei in a sample to undergo decay.

Question 4

Which type of radiation has the greatest penetrating power?

Accepted Answer

Gamma (γ)

Answer

Gamma radiation consists of high-energy photons with no mass or charge, giving it the greatest penetrating power — requiring lead or thick concrete to shield.

Question 5

What does the mass number (A) of a nucleus represent?

Accepted Answer

Total number of protons and neutrons

Answer

The mass number (A) is the total count of nucleons (protons + neutrons) in the nucleus of an atom.

Chemistry Practice Test Practice Test

Chemistry Practice Test Practice Test

Chemistry Test Nuclear Chemistry