Shapes of molecules Flashcards
(36 cards)
How do you calculate the shape of a molecule?
- what is the central atom
- which group on the periodic table is it in?
- how many bonds does it make?
- does it have any electrons/charge?
- bonds + e-
- divide by 2
- ans = number of e- pairs
2 bond pairs
no lone pairs
bong angle = 180°
shape = linear
3 bond pairs
no lone pairs
120°
trigonal planar
4 bond pairs
no lone pairs
109.5°
tetrahedral
5 bond pairs
no lone pairs
120° & 90°
trigonal bipyramid
6 bond pairs
no lone pairs
90°
octahedral
linear
no lone pairs
2 bond pairs
180°
trigonal planar
no lone pairs
3 bond pairs
120°
tetrahedral
no lone pairs
4 bond pairs
109.5°
trigonal bipyramid
no lone pairs
5 bond pairs
120° & 90°
octahedral
no lone pairs
6 bond pairs
90°
for each lone pair you subtract (….) from the bond angle
2.5°
2 bond pairs
1 lone pair
118°
bent OR non linear
3 bond pairs
1 lone pair
107°
trigonal pyramid
2 bond pairs
2 lone pairs
104.5°
bent OR non linear
4 bond pairs
1 lone pair
119° & 89°
3 bond pairs
2 lone pairs
120° OR 89°
trigonal planar OR T-shape
5 bond pairs
1 lone pair
89°
square pyramid
4 bond pairs
2 lone pairs
90°
square planar
lone pairs have a (……..) repulsive power than bond pairs
greater
lone pairs affect the bond angles by….
pushing the bonding pairs away
lone pair - lone pair is the (most/least/in between) repulsive
most
lone pair - bonding pair is the (most/least/in between) repulsive
in between
bonding pair - bonding pair is the (most/least/in between) repulsive
least
