Unit 3.5 Nuclear Decay (involves gambling) Flashcards
Nucleon formula???
(Describing the nucleus)
(Or actually, element layout)
A = Z + N
AXZ
Define A
(Describing the nucleus)
(2 things)
- Mass number
- N° of protons and neutrons in atom
Define Z
(Describing the nucleus)
(2 things)
- Atomic number
- N° of protons in atom
Define X
(Describing the nucleus)
(3 things)
- Atomic symbol
- Abbreviation used to represent
- atom in chemical formulas
Proton number = ?
(Describing the nucleus)
Same number of electrons
Define radioactivity?
(3-way)
- Spontaneous disintegration
- of an unstable nucleus
- within an atom
Define radioactive emission?
(3-way)
- An attempt by the unstable nucleus
- to become more stable
- by emitting 3 types of radiation
What are the 3 types of radiation emitted during radioactive emission?
- Alpha
- Beta
- Gamma
What are the 2 things that stability/instability of the nucleus depend on?
- N° of nucleons
- Ratio of protons to neutrons
Skipped page 4…. probably not needed?
I’ll come back one day… or not?
What do they use to measure radiation?
A Geiger counter
How do Geiger counters’ work?
(4-way)
- Principle of incoming radiation ionising a gas
- by knocking out an electron
- from electron shell
- to create both negative + positive ion pair
How do u correct for background radiation?
(2-way)
- Subtracting the background count rate
- from the measured count rate
Correcting for background radiation expressed as a formula?
(Corrected Count rate) = [Measured Count rate] - [Background]
Describe the process of ionization?
(2-way)
- Addition/removal of an electron
- to gain an ion
How do them ionization cloud chambers work?
(Fix-up)
- Dry ice needed to crate a ‘supersaturated’ environment
- Cools the alcohol vapour
- Radiation ionizes the vapour - condensing the alcohol along the radiation paths
Why do beta particles produce poorly defined curved tracks?
(Ionisation within “cloud chamber”)
(2 things)
- Less ionizing
- Curved due to less mass
Why do alpha particles produce well-define, thick straight tracks?
(Ionisation within “cloud chamber”)
(2 things)
- More ionizing
- Has more mass
Why do gamma rays leave virtually no trail?
(Ionisation within “cloud chamber”)
Very low ionizing ability
What stops alpha?
Tissue/cm of air
What stops beta?
mms of aluminium
What stops gamma?
Metres of concrete/cm’s of lead
How can an electric field be used to classify the different types of radiation?
(2-way + 2 things)
- Beta = negative electron ∴ positive attract
- Alpha = positive ∴ goes to negative
- Alpha also heavier ∴ deflection = less
- Gamma = no charge ∴ no deflection
Describe each finger for Fleming’s hand rule?
(3 fingers)
Thumb = motion
Index = magnetic field
Middle = current flow direction
Which hand do u use alpha on?
Left hand
Which hand do u use beta on?
Right hand
How can a magnetic field be used to classify the different types of radioactive emission?
(3 separations)
- Alpha rays = slightly deflected in 1 direction
- Beta rays = deflected strongly in opposite direction
- Gamma rays = not deflected
Describe alpha decay?
(4 things)
- Helium atom
+ - -4 on mass number
- -2 on atomic number
Describe beta decay?
(3 things & 2 +’s)
- Beta (-1 atomic number)
+ - +1 on atomic number
+ - V?
Describe beta+ decay?
(3 things? & 2 +’s)
- Beta+ (+1 atomic number)
+ - -1 on atomic number
+ - V?
Describe radioactive decay?
(2 things + 2-way)
- Spontaneous, no trigger to cause it
- Random occurrence
- Impossible to predict
- when individual nucleus will disintegrate
What is activity (A) of a sample defined as?
N° of disintegrations per unit time
What is the unit of activity?
Becquerel
(Bq)
1 Bq = ?
1 disintegration each second
What is decay constant generally?
(More needed, i hate logs)
Rate of change
A crazy gamble, Will finish later, HOWEVER, the next part is literally just logs
Is this gonna be a good gamble?
or ask for help before it terrorizes
So, i’m gonna gamble here only so i can save time, tho, might not be the best decision….
Don’t state here logs, i shall learn that separately on the whiteboard…. assuming i do that, ppq in addition to that. Shall truly be the crutch here (╯˘ -˘ )╯
Define mole
(3-way)
- The amount of substance that contains…
- the same n° of particles
- as there is in 12g of Carbon-12
So u know Avagadro’s constant NA, what about that?
(2 things?)
- One mole of any substance
- contains NA particles which is 6.02 x 1023
How do u find the molar mass of C or U?
(Of carbon or uranium)
You just…. look at the n° above…. “not the atomic number”
Formula for number of moles?
N° of moles = Mass of sample/Mass of 1 mole
n = M/Mmolar
Formula for number of particles?
(BIG DIFFERENCE)
N° of particles = Mass of sample/Mass of 1 particle
N = M/m
Once again, rlly bad last minute revision again. Surprisingly capacitance its like the knowledge retained at the back of my brain.
Just follow the plan.
