Chemical Bonding

Question 1

dot and cross diagram of polyatomic ion

Answer 1

[SO4]²⁻- the more electronegative one gains
[NH4]⁺- the less electronegative one loses

Question 2

single bond

Answer 2

1 sigma bond

Question 3

double bond

Answer 3

1 sigma + 1 pi bond

Question 4

triple bond

Answer 4

2 pi + 1 sigma bond

Question 5

sigma bond orientation

Answer 5

head to head

Question 6

pi bond orientation

Answer 6

side to side

Question 7

0 lone pair 2 bond pair

Answer 7

linear, 180°

Question 8

0 lone pair 3 bond pair

Answer 8

trigonal planar, 120°

Question 9

1 lone pair 2 bond pair

Answer 9

bent, 118°

Question 10

0 lone pair, 4 bond pair

Answer 10

tetrahedral, 109.5°

Question 11

1 lone pair, 3 bond pair

Answer 11

trigonal pyramidal , 107.5°

Question 12

2 lone pair, 2 bond pair

Answer 12

bent,105.5°

Question 13

0 lone pair, 5 bond pair

Answer 13

trigonal bipyramidal, 90° and 120°

Question 14

strength of bonds

Answer 14

idid - weakest
pdpd- middle
h-bond - strongest

Question 15

polar

Answer 15

has net dipole moment, think of it as has resultant force

Question 16

non-polar

Answer 16

no net dipole moment, no resultant force

Question 17

net dipole moment direction

Answer 17

from less E.N to more E.N

Question 18

idid bonds

Answer 18

1. ease of distortion of electron cloud:

↑ Mr , ↑ size of electron cloud, dipoles are more easily induced, ↑ energy needed, ↑ boiling point

2. surface area of contact between molecule if same Mr, straight has larger S.A than isomers so dipoles more easily induced

Question 19

Hydrogen bonding

Answer 19

protonic H bonded to F/O/N

Question 20

covalent compound w simple molecular structure properties

Answer 20

1. Low melting and boiling points
2. Non-conductors of electricity
3. Insoluble in water

Question 21

strength of intermolecular forces

Answer 21

h bond>pdpd ( only for polar)>idid

Question 22

factors affecting bond strength of metallic bond

Answer 22

1. no of delocalised electron
   ↑ electron ↑strength
   2.if same no of delocalised electron, based on 1/ ionic radius .
   ↑ radius↓strength

Question 23

metal propoerties

Answer 23

high melting and boiling pt
hard
good electrical conductor
malleable
soluble in other metals

Question 24

factors affecting strength of ionic bonds

Answer 24

1.lattice energy: product of charge of ions/ interionic distance
2.largest lattice E:↑ product of charge of ions↓interionic distance

Question 25

properties of ionic compound

Answer 25

high melting pt and boiling pt
hard and brittle
soluble in water
cant conduct electricity in solid/can conduct in molten and aq states
soluble in water

Question 26

factors affecting strength of covalent bond

Answer 26

1. ↑ bond order ( 3>2>1),↑ attraction
2. more effective orbital overlap- decreases with larger atomic size, increases with greater % of s

e.g. sp= 1/2,sp²=1/3 (weaker)

Question 27

physical properties of covalent compounds with simple molecular structure

Answer 27

low melting boiling pt
soluble in non polar solvents

Question 28

physical properties of covalent compounds with giant molecular lattice structure , diamond , graphite, silicon, silicon oxide

Answer 28

very high melting pt
non electrical conductor
hard
insoluble in all

Question 29

1 lone 4 bond

Answer 29

seesaw ,90° and 120°

Question 30

2 lone 3 bond

Answer 30

T shaped ,90°

Question 31

3 lone 2 bond

Answer 31

Linear 180°

Question 32

0 lone 6 bond

Answer 32

Octahedral, 90°

Question 33

1 lone 5 bond

Answer 33

square pyramidal , 90°

Question 34

2 lone 4 bond

Answer 34

square planar 90°