| what effect does beta decay have on atomic and mass number of an atom | atomic number increases by 1
mass number remains unchanged |
| what are isotopes | atoms of the same element with different mass numbers |
| what are the three types of radioactive decay | alpha
beta
gamma |
| what is the function of radioactive decay | it makes atoms more stable |
| what does an alpha particle consist of | two protons and two neutrons (a helium nucleus) |
| what is released during alpha decay | an alpha particle is released |
| what effect does alpha decay have on atomic and mass number of an atom | atomic number is reduced by two
mass number is reduced by four |
| what is a beta particle | a fast moving electron |
| what is released during beta decay | a beta particle
a neutrino |
| what effect does beta decay have on atomic and mass number of an atom | atomic number increases by 1
mass number remains unchanged |
| what is released during gamma emission | a high energy photon of electromagnetic radiation |
| what effect does gamma emission have on atomic and mass number of an atom | mass number + atomic number remain unchanged
gamma photons are part of the electromagnetic spectrum so have no mass or charge |
| what is nuclear fusion | when two smaller nuclei combine to form a larger nucleus |
| where does nuclear fusion take place | in our sun and other stars |
| what happens to the products of fusion | they gain kinetic energy which can be harnessed |
| name an equation that links energy and mass | E=mc^2
E is energy in joules
m is mass in kg
c is the speed of light |
| what is nuclear fission | when a large unstable nucleus splits into two smaller nuclei |
| what is released when fission takes place | neutrons |
| what are the two types of nuclear fission | spontaneous
induced |
| describe spontaneous nuclear fission | a natural process in which a large nucleus splits into two smaller nuclei
resulting in the release of neutrons that will not be contained in the two smaller nuclei |
| describe induced nuclear fission | when a large nucleus is bombarded with neutrons and absorbs one of them, making the nucleus very unstable and causing it to split |
| how can you tell from an equation that fission is induced | there is a neutron present on the left side |
| what happens to the products of nuclear fission | they gain kinetic energy
this energy is harnessed in nuclear power stations |
| what is meant by binding energy | energy required to hold nucleons (components of a nucleus) together as a nucleus
a nucleus is made of protons and neutrons, and there are forces of repulsion between the positive protons in the nucleus, so energy is required to hold the nucleus together |
| iron has a mass number of 56 and is one of the most stable of all the elements. what does this tell you about its binding energy? | it has a high binding energy per nucleon |
| what is meant by mass defect | the difference between the total mass of a nucleus and the total mass of nucleons that make up the nucleus
OR
the difference in mass between products and reactants during a nuclear reaction
it is equivalent to binding energy of the nucleus |
| are elements with lower and higher mass numbers (per nucleon?) more or less stable than others | less stable |
| what are the benefits of fusion over fission | the amount of energy released in a fusion reaction is vastly greater than in a fission reaction
it does not produce radioactive waste
safer as fission can cause explosions/fire
fuel is more abundant (hydrogen) |
| why do fusion and fission produce energy | the mass of the products is less than the mass of the reactants, there is a mass defect.
this mass is converted to energy in accordance with e=mc^2 |
