8.2 Nuclear instability

• The strong nuclear force holds protons and neutrons together in the nucleus
• Beta decay involves the emission of a beta particle and a neutrino
• Stable nuclei always have a 1:1 neutron to proton ratio.

  False
• In alpha decay, the atomic number decreases by 2
• What type of particle is emitted in alpha decay?

  Alpha particle
• The mass number decreases by 4 during alpha decay.

  True
• What particles are emitted in beta-minus decay?

  Electron, antineutrino
• The mass number changes in beta-minus decay.

  False
• In beta-plus decay, the atomic number of the nucleus decreases by 1
• What is nuclear instability?

  Insufficient strong nuclear force
• What particle is emitted in alpha decay?

  Alpha particle
• Steps leading to nuclear instability

  1️⃣ Electrostatic repulsion between protons increases

  2️⃣ Strong nuclear force becomes insufficient

  3️⃣ Neutron to proton ratio becomes imbalanced

  4️⃣ Radioactive decay occurs
• What is the composition of an alpha particle?

  Two protons, two neutrons
• What are the two types of beta decay?

  Beta-minus and beta-plus
• In alpha decay, the atomic number of the nucleus decreases by 2
• Match the type of beta decay with its characteristic:

  Beta-minus decay (β⁻) ↔️ Neutron converts to proton

  Beta-plus decay (β⁺) ↔️ Proton converts to neutron
• In beta-minus decay, the atomic number of the nucleus increases by 1
• What particles are emitted in beta-plus decay?

  Positron, neutrino
• Beta decay adjusts the neutron-to-proton ratio in the nucleus.


  True
• A balanced neutron-to-proton ratio leads to nuclear stability.


  True
• What is the approximate range of the strong nuclear force?

  10⁻¹⁵ m
• Gluons are the carrier particles of the strong nuclear force.


  True
• The weak nuclear force has a very short range of less than 10⁻¹⁷ m
• What happens to a nucleus when the neutron to proton ratio is not optimal?

  Radioactive decay
• What do unstable nuclei undergo to achieve a more stable configuration?

  Radioactive decay
• In alpha decay, the atomic number decreases by 2 and the mass number decreases by 4.


  True
• What are the two primary types of beta decay?

  Beta-minus and Beta-plus
• Beta-minus decay increases the atomic number by 1 and leaves the mass number unchanged.


  True
• In beta-plus decay, what particles are emitted?

  Positron and neutrino
• In beta-plus decay, a proton converts into a neutron, emitting a positron and a neutrino.
• Beta-plus decay decreases the atomic number by 1 and leaves the mass number unchanged.


  True
• Gamma decay changes the atomic number and mass number of the nucleus.

  False
• Radioactive decay follows an exponential decay law, described by the equation N(t) = N₀e^(-λt), where λ is the decay constant.
• What is radioactive decay used in radioactive dating techniques to determine?

  Age of ancient artifacts
• What causes nuclear instability in a nucleus?

  Excess electrostatic repulsion
• The strong nuclear force is the strongest of the fundamental forces.
• The strong nuclear force holds the nucleus together.
• How does the strength of the weak nuclear force compare to the strong nuclear force?

  Weaker than strong force
• Match the neutron to proton ratio with its effect on stability:

  Optimal ratio ↔️ Stable nucleus

  Ratio too high or low ↔️ Unstable nucleus
• Alpha decay results in a new element with a lower atomic number and mass number.

  True