1.26 shapes of molecules

Question 1

which shape is formed from 6 electron pairs, 2 non-bonding?

Answer 1

square planar

Question 2

what are the bond angles in a T-shaped molecule?

Answer 2

less than 90 and 120

Question 3

which shape does 5 electron pairs, 2 non-bonding, form?

Answer 3

T -shaped

Question 4

what is the bond angle in an angular shape?

Answer 4

105 degrees

Question 5

which shapes does 4 electron pairs, 2 non-bonding, form?

Answer 5

angular

Question 6

what is the bond angle in a trigonal pyramidal shape?

Answer 6

107 degrees

Question 7

which shape does 4 electron pairs, one non-bonding, form?

Answer 7

trigonal pyramidal

Question 8

how can you determine if there are any non-bonding pairs?

Answer 8

by subtracting the number of atoms around the central atom from the number of pairs

Question 9

in which order do repulsive effects decrease?

Answer 9

non-bonding : non-bonding > non-bonding : bonding > bonding : bonding

Question 10

why do non-bonding pairs from distorted shapes?

Answer 10

they have a greater repulsive effect than bonding pairs

Question 11

what is a dative bond?

Answer 11

when both electrons come from the same atom

Question 12

what is the bond angle in an octahedral shape?

Answer 12

90 degrees

Question 13

what are the bond angles in a trigonal bipyramidal shape?

Answer 13

90 (between planar and upper part) and 120 (between planar part)

Question 14

what is the bond angle in a tetrahedral shape?

Answer 14

109.5 degrees

Question 15

what is the bond angle in a trigonal planar shape?

Answer 15

120 degrees

Question 16

what is the bonding angle in a linear shape?

Answer 16

180 degrees

Question 17

which shape does 6 bonding electron pairs form?

Answer 17

octahedral

Question 18

which shape does 5 bonding electron pairs form?

Answer 18

trigonal bipyramidal

Question 19

which shape does 4 bonding electron pairs form?

Answer 19

tetrahedral

Question 20

which shape does 3 bonding electron pairs form?

Answer 20

trigonal planar

Question 21

which shape does 2 bonding electron pairs form?

Answer 21

linear

Question 22

what are the steps used to calculate the number of electron pairs around the central atom?

Answer 22

1. count the number of outer electrons on the central atom
2. add 1 for each atom attached to the central atom
3. add electrons if the ion is negative, subtract if it sis positive
4. divide the total number by 2

Question 23

what determines the shape of a molecule?

Answer 23

the number of electron pairs around the atom

Question 24

why do molecules adopt a particular shape?

Answer 24

to minimise the repulsive forces of the shared electrons in a covalent bond