Shapes of molecules/covalent bonding

Question 1

Bond angle and number of bond pairs in a linear molecule

Answer 1

180 degrees and 2 bond pairs

Question 2

Bond angle and number of bond pairs in a trigonal planar molecule

Answer 2

120 degrees and 3 bond pairs

Question 3

Bond angle and number of bond pairs in a tetrahedral molecule

Answer 3

109.5 degrees and 4 bond pairs

Question 4

Bond angle and number of bond pairs in a trigonal bipyramidal molecule

Answer 4

120 degrees and 90 degrees and 5 bond pairs

Question 5

Bond angle and number of bond pairs in a octahedral molecule

Answer 5

90 degrees and 6 bond pairs

Question 6

Give an example of a linear molecule

Answer 6

BeCl2

Question 7

Give an example of a trigonal planar molecule

Answer 7

AlCl3

Question 8

Give an example of a tetrahedral molecule

Answer 8

Methane

Question 9

Give an example of a trigonal bipyramidal molecule

Answer 9

PF5

Question 10

Give an example of a octahedral molecule

Answer 10

SF6

Question 11

What do lone pairs do

Answer 11

Lone pairs repel more than bonding pairs which causes distortion away from regular shapes.

Question 12

Bond angle and number of bond/lone pairs in a pyramidal molecule

Answer 12

1 lone pair and 3 bonding pairs. 107 degrees

Question 13

Bond angle and number of bond/lone pairs in a non-linear molecule

Answer 13

2 lone pairs and 2 bonding pairs. 104.5 degrees

Question 14

Bond angle and number of bond/lone pairs in a square planar molecule

Answer 14

2 lone pairs and 4 bonding pairs. 90 degrees

Question 15

Give an example of a pyramidal molecule

Answer 15

Ammonia (NH3)

Question 16

Give an example of a non-linear molecule

Answer 16

Water (H20)

Question 17

Give an example of a square planar molecule

Answer 17

Xenon tetrafluoride (XeF4)

Question 18

How can you work out an irregular shape

Answer 18

work out the number of bonding pairs, use this to find the regular shape and think of the effect on repulsion.

Question 19

How many bonds can Carbon form

Answer 19

4

Question 20

How many bonds can nitrogen form

Answer 20

3

Question 21

How many bonds can oxygen form

Answer 21

2

Question 22

How many bonds can Hydrogen form

Answer 22

1

Question 23

What rule do elements follow when covalent bonding and what are the exceptions

Answer 23

2,8,8. Boron, phosphorus, sulfur and chlorine

Question 24

What can phosphorus, sulfur and chlorine do

Answer 24

Hold up to 18 electrons because of the 3rd shell (2n2)

Question 25

What can boron do

Answer 25

Make 3 bonds leaving it with 6 electrons in outer shell

Question 26

What is a dative bond

Answer 26

A covalent bond where the pair of shared electrons has been donated by only one of the atoms.

Question 27

define ionic bonding

Answer 27

electrostatic attractions between positive and negative ions