Radioactivity (10) Flashcards
(85 cards)
At the centre of every atom is a _____________
Nucleus
The nucleus of an atom, contains __________ and ___________
Protons and neutrons
The nucleus of an atom makes up most of the _______ of the atom, but takes up virtually no __________
Weight Space
The electrons are _______________ charged and are really small
Negatively
The number of protons in the nucleus is called the ____________ number
Number of protons = atomic number
The total number of protons and neutrons in the nucleus is called the __________ number
Mass
What are isotopes
Atoms of the same element with different numbers of neutrons
Isotopes are atoms of the same __________ with different numbers of ___________
Element
Neutrons
This means that different isotopes have different __________ numbers
Mass numbers
Usually each element only has one or two ___________ isotopes
Stable
If the nucleus of an atom is unstable then it tends to be _____________. The unstable nucleus decays and emits _______________
Radioactive
Radiation
Radioactive decay is a ____________ process
Random
The nuclei of unstable isotopes break down at ___________. If you have 1000 unstable nuclei, you canβt say when any of one them is going to decay, and you canβt do anything at all to make a _________ happen
Random
Decay
Each nucleus decays spontaneously and is completely unaffected by physical conditions such as _________________ or ____________ bonding
Temperature
Chemical bonding
When a nucleus does decay it spits out one or more of the three types of radiation _________, ________ or __________
Alpha
Beta
Gamma
In the process of decay, the _________ often changes into a new element
Nucleus
There is (low level) background nuclear radiation all around us all the time which come from
Space
Substances on earth
Living things
Human activity (nuclear explosions)
Nuclear radiation causes ______________ by bashing into atoms and knocking _____________ off them. Atoms (with no overall _________) are turned into ______ (which are __________) - hence the term ionisation (being turned into ions)
Ionisation
Electrons
Charge
Ions
Charged
The further the radiation can penetrate before hitting an atom and getting stopped the _________ damage it will do along the way and so t?ββhe _________ ionising it is
Less Less
____________ radiation can be detected with a Geiger-Muller detector
Ionising
Alpha particles are made up of ___ protons and ___ neutrons
2 protons and 2 neutrons
What are the features of an alpha particle
Big, heavy, slow moving
What are the features of a beta particle
Quite fast, quite small
What are the features of a gamma particle
No mass - just energy
