Chapter 1 - Atomic Structure Flashcards
What are the 4 orbitals ?
4
- s
- p
- d
- f
What’s the exception for for the orbital rules ?
Order ?
(2)
- 4s subshell has lower energy level than 3D subshell
- so 4s subshell fills up first
How are line spectrum created ?
3
- electron shells are called quantum shells or energy levels
- ground state : Lowest energy possible
- if atoms take in energy from surrounding then they can move to higher energy levels further from nucleus (EXCITED)
- electrons release energy by dropping from higher energy level to Lower energy level
- energy levels = fixed value = discrete
Ionisation energy graph ?
Pattern
1
2,3,3
What 3 factors effect ionisation energy ?
(3)
(3)
- NUCLEAR CHARGE -more protons = stronger attraction to Electrons
- ELECTRON SHELL -attraction decreases with distance
- SHIELDING-as number of electrons between outer shell and nucleus increase - less attraction
What’s the first ionisation energy ?
2
- is the energy needed to remove 1 electron from each atom in 1 mole of gaseous 1+ atoms
How do you write the first ionisation energy equations?
2
O —> O+ + e-
What’s the meaning of a high ionisation energy ?
2
- strong attraction between the electron and the nucleus
- so more energy is needed to overcome the attraction and remove electron
What happens to first ionisation as you go down the group ? Whyyyy?
- ionisation energy DECREASES
- more shells
- atomic radius increases
- shielding increases energy
what is relative atomic mass(2)
- masses of atoms compared to C12
- relative atomic mass = an average of all the relative isotopic masses so its not usually a whole number
what rules do electron follow when filling up energy levels
3
- electrons go into the orbital with the lowest energy level first
- each orbital contains at most 2 electrons
- when there are two or more orbitals at the same energy level - they fill up singly before electrons pair up
How is relative abundance measures in a mass spectrometer ?
3
- ions hit detector and cause current
- electrons cause electron flow
- current and electrical signal is related to abundance
Why is there a drop in first ionisation energy between group 2/3 ?
Use Mg and Al as examples …
(4)
- Mg: 1s2 2s2 2p6 3s2
- Al: 1s2 2s2 2p6 3s2 3p2
Al -outer electron in 3p orbital rather than 3s
= further away
=additional shielding
Why is there a drop in first ionisation energy between group 5/6 ?
- P AND S
(6)
P- 1s2 2s2 2p6 3s2 3p3
S-1s2 2s2 2p6 3s2 3p4
-S is lower than P
- the shielding of both element is the SAME
-electron in P is removed from SINGLY applied orbital ⬆️
-electron removed from S from shared orbitals ( easier to remove) ⬇️⬆️
= Mutual repulsion between paired electrons
Why is ionisation energy endothermic ?
2
- elements take in heat from the surroundings to overcome attraction between negative electron and positive nucleus …
