Atomic Structure Flashcards
Definition of relative atomic mass
Average mass of an atom on a scale where an atom of carbon-12 is 12
Definition of relative isotopic mass
Mass of at atom of an isotope where an atom of carbon-12 is 12
Definition of relative molecular mass
Average mass of a molecule on a scale where an atom of carbon-12 is 12
What are the 4 steps of mass spectrometry
Ionisation, acceleration, iron drift, detection
Ways of Ionisation
Electrospray
Electron impact
Electrospray ionisation
Sample dissolved and pushed through a small nozzle at high pressure
High voltage
Gains H+ ion
Electron impact ionisation
Sample vaporised
Electron gun is used to fire high energy electrons
Knocks one electron off so becomes 1+ ions
Why is the sample accelerated in mass spectrometry
To have the same kinetic energy
Lighter ions will move faster than heavier ones
How many electrons in the s subshell
2
How many orbitals in the s sub shell
1
How many electrons in the p subshell
6
How many orbitals in the p subshell
3
How many electrons in the d subshell
10
How many orbitals are there in the d subshell
5
Which elements donate one of their 4s electrons to 3d subshell and why
Chromium and copper
As they are better with a more stable full or half full d sub shell
What happens with transition metals when they become ions in the 4s oribital
They loose electrons from their 4s electrons before their 3d electrons
Definition of first ionisation energy
Is the energy needed to remove 1 electron from each atom in 1 mole of gaseous atoms to form 1 mole of gaseous 1+ ions
What type of reaction is the first ionisation energy
Endothermic (+)
What are the factors affecting ionisation energy
Nuclear charge
Distance from nucleus
Shielding
Definition of the second ionisation energy
The energy needed to remove 1 electron from each ion in 1 mole off gaseous 1+ ions to form 1 mole of gaseous 2+ ions
Why does ionisation energys increase within each shell
Electrons being removed from an increasingly positive ion so less repulsion amongst the remaining electrons
Why are there big jumps in ionisation energys
Happen when a new shell is being broken into
Electron is being removed from a shell closer to the nucleus
What happens to the first ionisation energy as you go down a group
Decrease
What happens to the first ionisation across a period
Generally increase
why does the ionisation energy decrease as you go down group 2
As you go down, extra electron shell is added, extra shielding and further away
Why does ionisation increase across a period
Number of protons increases, so stronger nuclear attraction.
