Atomic Structure Flashcards
Atomic Number
No. p (in nucleus of) an atom
Mass Number
Total no. p + n (in nucleus) of atom
RAM
av. (weighted mean) mass of an atom of an el. rel to 1/12th mass of an atom of C-12
RIM
mass of an atom of an isotope of an el rel to 1/12th mass of an atom of C-12
RMM
Mass (weighted mean) of one molecule relative to 1/12th mass of an atom of C-12
RFM
av (weighted mean) mass of a formula unit relative to 1/12th mass of an atom of C-12
Orbtial
Region within an atom that can hold up to 2e with opposite spins
S subshell
One s orbital
Holds up to 2e
P subshell
3p orbitals
Holds up to 6e
D subshell
5 orbitals
Holds up to 10e
What order do the subshells fill in?
1s,2s,2p,3s,3p,4s,3d,4p
What order are the subshells written in?
1s,2s,2p,3s,3p,3d,4s,4p
What is the e config of CU:
1s2,2s2,2p6,3s2,3p6,3d10,4s1
What is the e config of CR:
1s2,2s2,2p6,3s2,3p6,3d5,4s1
What is first ionisation of en?
En req to convert one mole of gaseous atoms into gaseous ions with a single positive charge
What is the second ionisation en?
En req to convert one mole of gaseous ions with a single positive charge into ions with a double positive charge
What is the third ionisation en?
En req to conv one mole of gaseous ions with a double positive charge into ions with triple pos charge
What happens to first I.E across a period and down a group?
Across a period- 1st I.E en gen increases
Down a group- first I.E decreases
Why does I.E increase across a period?
Increase in nuclear charge
Decrease in atomic radius
Why does I.E decrease down a group?
Increase in atomic radius
Increase in shielding
Why does N2 have a higher I.E than O2?
N2: 1s2,2s2,2p3- has half filled 2p subshell
O2 atom: 1s2,2s2,2p4- has more than half filled 2p subshell
Half filled 2p subshell is more stable
