radioactivity

what are the three things in an atom

proton

neutron

electron

what is the atomic number in an atom

shows number of protons in an atom

what is the atomic mass show in the atom

shows number of protons and neutrons in an atom

define isotope

version of an atom that has same number of protons but a different number of neutrons 

what are the three ionising radiations

Alpha radiation

Beta radiation

Gamma radiation

what is alpha radiation, what does it take out of an atom, what is the penetrating power and what is the ionising affect

in alpha radiation it takes out two protons and two neutrons, the penetrating power is low and the ionising affect is high.

in beta radiation, what does it take out of an atom, what is the penetrating power and what is the ionising affect

beta radiation takes out an electron, the penetrating power is medium and the ionising affect is medium.

in the gamma radiation what doe it take out, what is the penetrating power and what is the ionising affect

gamma radiation takes out gamma waves, the penetrating power is high and the ionising affect is low.

what is the ionising affect 

the ability of radiation to knock out electrons causing a charged ion 

using the penetrating power data, what material blocks alpha 

paper 

using the penetrating power data, what material blocks beta

aluminium

using the penetrating power data, what material blocks gamma

lead

what is the atomic and mass change for alpha

atomic number decreases by two

atomic mass decrease by four 

what is the atomic and mass change for beta

atomic number decreases by one

mass doesnt change 

atomic number changes since atomic number protons have the same number of electrons, and beta takes out an electron meaning a proton will do as well. 

what is the atomic and mass change for gamma 

none only loses energy

in beta radiation how can you balance the equation of

since beta releases an electron and it is negative, the atomic number has to be 6 + 1 = 7 to balance it.

for alpha radiation how can you balance the equation of

since we know that alpha radiation releases two protons and two neutrons that must be the atomic number is 2 and the atomic mass is 4, so we do 88-2 and 226-4 to balance it

how does neutron emission change the atomic number and atomic mass

doesn’t change atomic mass but changes atomic mass by decreases one. 

how can you detect ionising radiation

photographic film - darkens when exposed to radiation

geiger muller detector - produces a click sound when radiation ionises

what is the sources of background radiation

rocks (natural radiation)

high energy particles from sun (cosmic rays) 

plants (bananas)

what is background radiation 

ionising radiation that is always present in our environment 

in ionising radiation, what is the unit for when a nucleus is unstable and emits something then decays

becquerels (Bp)

explain over time would becquerels decrease or increase

decrease because its unlikely for the nuclei to stay unstable for a period of time

define half life

half life is the time that it takes for half the nuclei to decay OR for activity to half

define activity half

the number of nuclei to decay in ever period of time.

A radioactive source has an initial activity of 960 Bq. The half-life of the isotope is 4 minutes. What is the activity after 12 minutes?

960, 480, 240, 120

what is the use of radioactivity medically 

radiotherapy (high does of gamma rays that kill cancer cells)

medical tracers (radioactive isotope that is swallowed, then it emits gamma rays to give an diagnosis image)

sterilisation (sterilise medical equipment without using heat)

what is the use of radioactivity in the industries

thickness control- beta particles used in paper/metal to monitor thickness (thickness of the material that is between the beta particles and the detector

leak detection (can detect leaks in pipelines)

define contamination

when a radioactive material moves to another object or substance.

define irradiation

being exposed to a radioactive material without being in contact with the radioactive material.

what are the dangers of ionising radiation 

damage living organisms DNA → causing mutations 

damage cells and tissue 

if radioactive material/waste stays radiactive for 1000 of years causing environmental contamination