1.2 Basic Idea about Atoms Flashcards
(46 cards)
Show alpha emission towards an element?
Well it changes to an entirely new element
Atomic mass is minused by 4
Atomic number is minused by 2
The alpha particle produced = 4, 2 He^2+
Show beta emission towards an element?
Ig they all change to an entirely new element
Atomic mass stays the same however
Atomic number increased by 1 cuz
Beta particle is an electron = B-
Explain positron emission
aka beta plus decay
(when proton inside nucleus = neutron + positron <- positive electron)
Electron neutrino also emitted
e.g.
23,12Mg –> 23,11Na + 0,+1e + 0,0v <– greek edition
Explain electron capture
- Nucleus absorbs inner-shell electron
- Electron + proton = neutron
- Electron neutrino emitted
- Inner shell electron vacancy replaced by electron from outer shell
- Excess energy of falling electron sometimes emitted as X-ray
- This is auger emission
- Sometimes excess energy of falling electron carried away by outer electron being emitted
- Daughter isotope produced will then form as positive ion
or just look at page 5….
e.g.
81,36Kr + 0,-1e -> 81,35Br + 0,0v <– greek edition
Where will alpha go in that magnetic field
Down (-ve) Cuz it got 2+ charge but Mr of 4 = weakly deflected
Where will beta go in that magnetic field
Up (+ve) Cuz it got -1 charge + small mass = strongly deflected
Where will gamma go in that magnetic field
No deflection = no mass/charge
What stops alpha?
Sheet of paper
What stops beta?
Few mm of aluminium
What stops gamma?
Few cm of lead
Simple term of half life
Time taken for something to half its quantity
Look at page 8 onwards for half life related shit
Okay
Explain effects of radiation towards atoms simply
It shall ionise atoms = dmg DNA and cause mutations, cancer or leukaemia
Explain effects of radiation towards atoms complexingly?
(3 steps)
- Ionizing radiation enough energy to remove electrons
- From atoms that make up the tissues n stuff
- Breaks chemical bonds
Ima stick with that
Explain Radio-Carbon Dating
Carbon-14 dating used to determine age of certain stuff.
Has half life of 5700 years
Doesn’t decay easily so ye ig?
Whats so interesting about gamma
Many medical uses I cba to explain but u can look at page 13 and onwards
Whats nuclear charge?
Number of protons?
but it’s also how strong their attractive force is between electrons
If nuclear charge increases, i.e will?
Ionisation energy increases
What may usually control i.e
The distance of an electron from the nucleus
Explain electron shielding
When first electron in shell is more further away from nucleus
Cuz more protection from nuclear charge by inner electron shells
If electron shell further away from nucleus, i.e will?
Become smaller
Definition of electron shielding?
The repulsion between electrons in different shells.
If shielding increases, effective nuclear charge ??? & I.E ????
They both decrease
If nuclear charge increase and shielding the same, I.E ???
Increases
