Atomic Structure 🤗 Flashcards
How many stable forms of isotopes do elements have
1 or 2
What do unstable isotopes do and what procces is it called
Tend to decay into other elements and give out radiation as they try to become more stable radioactive decay
What do radioactive substances give out
One or more types of ionising radiation from nucleas and somtimes neutrons
What is ionising radiation and what is ionising power
Radiation that knocks electrons electrons off atoms creating positive ions
The ionising power of radiation is how easy it can do this
Properties of alpha particles
Are helium nuclei
Absorbed by sheet of paper
Due to size very ionising
Where are alpha particles used
Smoke detectors -ionises air particles causing current to flow ,if smoke is in air it binds to the ions meaning the current stops causing an alarm to sound
Properties of beta particles
Are high speed electrons
Moderately ionising
Absorbed by aluminium
For every beta particle emitted a neutron in the nucleus has turned into a proton
What are beta particles used in
To test the thickness of metal
Slight variations in thickness affect the amount of radiation passing through the sheet
Gamma rays properties
Realeased by nucleus
Penetrate far into materials
Weakly ionising bc they tend to pas through rather than collide with atoms
Can be absorbed with thick sheet of lead or concrete
How do you show the nuclear equation
Atom before decay->atom after decay+radiation emitted
How does alpha decay decrease the charge and mass of nucleus
When atom emitted alpha particle it’s atomic number reduces by 2 and mad number by 4
How does beta decay increase the charge of nucleus
Due to nucleus lost a neutron and gained a proton during beta decay
Mass number does not change
Why do gamma rays not change the charge or mass of the nucleas
Due to them being a way to get rid of excess energy from nucleas
What gives out radiation
Radioactive substances give it out no matter what
How can radiation be measured and what is a count rate
Geiger miller tube and counter which records the count rate
Count rate being the number of radiation counts reading it per second
Radioactive decay is entirely what ?
Random you can predict which nucleas In a sample will
decay next or when
What is a half life
The amount of time it takes for the radioactivity emitted by a source to halve it can be used to make predictions
What is rate decay in source measured in
Bq -1 decay per second
What are the risk to using radiations
Can enter living cells and ionise atoms within them
Can damage cells and cause cancer
What is exposure to radiation called and what happens
Irradiation
This does not make it radioactive
Keeping sources in lead lined boxes is a way of reducing irradiation
What is contamination and what’s the problems of it
Radioactive particles getting into objects
The contaminating atoms might then decay and could cause you harm
Gloves and tongs should always be used when handling sources
What happens when irritation by gamma beta and alpha radiations
Beta and grammar penetrate body and get to delicate organs
Alpha is less dangerous due to it not penetrating skin
High levels of irradiation from all sources are dangerous
How do the different rations effect contamination
Inside body alpha is most dangerous due to all damage being very localised
Beta is less damaging inside body as it’s absorbed over a wider areas
Gamma is the least dangerous due them mostly massing stright through
