technology to detect radioactivity and the development of atomic theory

Question 1

What is radioactivity?

Answer 1

radioactivity - the emission of radiation from an unstable atom
This behaviour is displayed when there are large unstable atoms. If an atom is unstable, there are more neutrons than protons, making the nucleus fall apart.

Question 2

What are the three nuclear radiation

Answer 2

gamma, beta and alpha radiation

Question 3

What is gamma radiation?

Answer 3

Gamma
A gamma ray (g) is a packet of electromagnetic energy (photon) emitted by the
nucleus of some radionuclides following radioactive decay. Gamma photons are
the most energetic photons in the electromagnetic spectrum.

Question 4

What is Alpha decay?

Answer 4

Alpha decay occurs when an atom has too many neutrons making it unstable

Emits energy and alpha particle which loses protons and neutrons making it stable

This creates a helium nucleus which contains 2 protons and 2 neutrons

Question 5

What is beta radiation?

Answer 5

Beta
Beta particles are high-energy, high-speed electrons or positrons emitted by certain fission fragments or by certain primordial radioactive nuclei such as potassium-40. The beta particles are a form of ionizing radiation also known as
beta rays. The production of beta particles is termed beta decay.

Question 6

Explain how Ernest Rutherford contributed to the development of the atomic theory?

Answer 6

Contribution and experimentation

Ernest Rutherford, a scientist, discovered the atomic nucleus using alpha radiation and a piece of gold foil in 1911. He did this by putting a screen around the gold thin foil. Using the alpha particle emitter, it went through the slit of the screen allowing it to hit the foil from the beam of particles.