Fission and fusion Flashcards
What are nuclear fission and fusion?
Nuclear fission and fusion are nuclear reactions that change the nucleus of an atom to produce high amounts of energy from the energy stored in the nucleus.
Define nuclear fission.
The splitting of a large, unstable nucleus into two smaller nuclei.
What initiates the process of nuclear fission?
A neutron collides with an unstable nucleus.
What are the reactants in a nuclear fission reaction?
The neutron and the unstable nucleus.
What are the products of nuclear fission? (3)
- Two smaller nuclei (daughter nuclei)
- two or three neutrons
- Gamma rays.
What happens during a nuclear fission reaction?
A neutron is fired into the target nucleus, causing it to split.
Write the nuclide equation for the fission of uranium-235.
U₉₂²³⁵ + n₀¹ → Kr₃₆⁹² + Ba₅₆¹⁴¹ + 3n₀¹ + energy.
What is the significance of uranium-235 in nuclear fission?
It is an unstable isotope of uranium that can decay by fission to produce smaller nuclei and neutrons.
How is energy conserved in a nuclear fission reaction?
The sum of the nucleon numbers of the reactants is equal to the sum of the nucleon numbers of the products.
What is observed about the mass of the products in a nuclear fission reaction?
The mass of the products is less than the mass of the original nucleus.
What is released during the fission process?
Energy, as the remaining mass is converted into energy.
What is nuclear fusion?
When two light nuclei join to form a heavier nucleus.
What is the primary fusion reaction occurring in stars?
Hydrogen nuclei are fused together to form a helium nucleus.
What conditions are required for nuclear fusion?
Extremely high temperature and pressure.
Write the nuclide equation for the fusion of deuterium and hydrogen.
H₁² + H₁¹ → He₂³ + energy.
What is deuterium?
An isotope of hydrogen with 1 proton and 1 neutron.
What is the relationship between mass and energy in nuclear fusion?
The mass of the product (fused nucleus) is less than the mass of the two original nuclei, as a small amount of mass is converted into energy.
How much energy is released from 1 kg of hydrogen during fusion?
It is equivalent to the energy from burning about 10 million kilograms of coal.
Calculate the number of neutrons, N, emitted in the fission reaction: U₉₂²³⁵ + n₀¹ → Rb₃₇⁹₆ + Cs₅₅¹³₇ + Nn₀¹.
N = 236 – 233 = 3.
What is the sum of the nucleon numbers of the reactants in the provided fission reaction?
236.
What is the sum of the nucleon numbers of the products in the provided fission reaction?
233 + N.
