Atomic structure

Question 1

Formula for deflection

Answer 1

charge/mass of what u want to find out
DIVIDE
charge/mass of given *degree

Question 2

Electron/quantum shell

Answer 2

each shell is given a principal quantum number
Larger n,
- Further e- from nucleus
- Less strongly e- bound to nucleus
- higher the energy level

Question 3

s orbital characteristic

Answer 3

1 type
spherical & non directional

Question 4

p orbital characteristic

Answer 4

3 types
dumbbell shaped, directional
px, py, pz along different axes

Question 5

z orbital characteristic

Answer 5

5 types
4 have four lobes (butterfly)
dz2 have donut shape
directional & diff orientation
dxy dyz dxz dx2-y2 dz2

Question 6

Aufbau principle

Answer 6

4s lower energy than 3d
4s fills up before 3d
4s has higher energy than 3d when filled
Remove e- from 4s 1st then 3d

Question 7

Hunds rule

Answer 7

Fill up orbitals singly first to minimise e- repulsion

Question 8

Configuration for Cr

Answer 8

1s2 2s2 2p6 3s2 3p6 2d5 4s1
extra stability w half filled 3d subshell

Question 9

Configuration for Cu

Answer 9

1s2 2s2 2p6 3s2 3p6 3d10 4s1
extra stability w fully filled 3d subshell

Question 10

First ionisation energy

Answer 10

First IE is the energy required to remove 1 mole of e- from 1 mole of gaseous atoms of element to form 1 mole of singly +ve charged gaseous ions
X (g) -> X+(g) + e-

Question 11

Second ionisation energy

Answer 11

2nd IE is the energy required to remove 1 mole of e- from 1 mole of singly +ve charged gaseous ions to form 1 mole of doubly +ve charged gaseous ions
X+ (g) -> X2+ (g) + e-

Question 12

What is nuclear charge?

Answer 12

Nuclear charge is the attractive force of protons in nucleus for electrons
- Higher no. of protons, stronger nuclear charge

Question 13

What is shielding effect?

Answer 13

Shielding of valence e- from electrostatic attraction of +ve charged nucleus by inner shell electrons

Inner shell e- shield valence e- more effectively than e- in same valence shell

as shielding effect increases, attraction of nucleus decreases, less energy required to remove e-

Question 14

What is effective nuclear charge?

Answer 14

ENC is combined effect of nuclear charge - shielding effect
NET electrostatic attraction betw. +ve charged nucleus & valence e- to be removed

Question 15

IE across period

Answer 15

Across period,
proton increases, NC increases
e- added to same valence shell, shielding effect relatively constant
ENC increases, stronger electrostatic FOA between nucleus & valence e-
More energy required to remove valence e-

Question 16

Deviation from trend for group 2 > 13, and 15>16

Answer 16

GROUP 2 > 13
Al has lower IE than Mg as 3p e- to be removed has higher energy (held less strongly) than 3s even tho same principle quantum shell
Less energy req. to remove 3p e- than 3s e-

GROUP 15 > 16
inter electron repulsion present in 2p/3p orbital
Less energy required to remove valence electron

Question 17

IE decreases down group

Answer 17

IE decreases down group
Proton increase, NC increase
No. of e- shells & shielding effect increases
Valence e- experience weaker eFOA to nucleus
Less energy required to remove e-

Question 18

Periodic transition from group 1 to 18

Answer 18

1st IE decreases alot from grp 18 to 1 of next period
Ne much higher than Na
Valence 3s in NA has stronger shielding effect due to additional inner shell of e- compared to 2p in Ne
3s in Na is further away from nucleus from nucleus, experience weaker eFOA to nucleus