radiation Flashcards
what are the three types of radiation
alpha radiation, beta radiation and gamma rays
how are alpha particles released from unstable isotopes
Alpha decay occurs most often in massive nuclei that have too large a proton to neutron ratio. Alpha particle(s) are released (containing two protons and neutrons) which creates alpha radiation.
how are beta particles released from unstable isotopes
Beta radiation occurs when there are too many neutrons. An excess neutron transforms into a proton and an electron. The proton stays in the nucleus and the electron is released, creating the radiation.
how are gamma rays released from unstable isotopes
which some unstable atomic nuclei dissipate excess energy. Gamma rays are emitted during nuclear fission in nuclear explosions.
properties of alpha particles
slow, heavy, highly energetic, positively charged, 2+ charge
properties of beta particles
high energy, negatively charged, fast moving (almost the speed of light) 1- charge
properties of gamma rays
large penetrating power, travel at the speed of light, small wavelengths, neutral charge.
materials that offer suitable protection from alpha particles and why this is
sheet of paper, skin, few inches of air. not much protection is required because even though they are highly energetic, they use up all their energy to travel short distances as they are so heavy and therefore lack the energy to penetrate even thin layers
materials that offer protection from beta particles and why
layer of clothing, thin layers, aluminium plate or foil. they need thicker ,materials because they can travel far into a material before interacting with an atom enough for its energy to be fully absorbed.
materials that offer protection against gamma rays and why
thick or dense material, lead, concrete, wood. This is because they have no electric charge and thus do not interact with matter as strongly as do charged particles.
biological effects of radiation
High radiation doses kill cells. Living cells exposed to radiation could: (1) repair themselves, leaving no damage; (2) die and be replaced, much like millions of body cells do every day; or (3) incorrectly repair themselves, resulting in a biophysical change. High doses can kill so many cells that tissues and organs are damaged immediately. This in turn may cause a rapid body response often called Acute Radiation Syndrome.
effects of radiation on the environment
just like in humans, radioactive material can damage plant tissue as well as inhibit plant growth. Radioactive material in soil can prevent nutrient from being taken in by plants, causing it to be infertile. It can also harm the cells in animals, just like humans.
