Shapes of molecules?

Created by

Erin Jeavons

Cards (26)

2,0 
Linear
180 degrees
3,0 
Trigonal planar
120 degrees
4,0 
Tetrahedral
109.5 degrees
5,0 
Trigonal bipyramidal
120/90 degrees
6,0 
Octahedral
90 degrees
What angel do lone pairs decrease bond angles by?
2.5 degrees
3,1 
Trigonal pyramidal
107 degrees
3,2 
T shape
87.5 degrees
2,1
Bent
117.5 degrees
4,1 
Seesaw
117.5/87.5 degrees
4,2 
Square planar
90 degrees
CO2
Linear
180 degrees.
SO2
Bent
117.5 degrees
SO3
Trigonal planar
120 degrees
What do lone pairs have?
Greater charge density so greater repulsion.
Lone pairs are electrons in outer shell, not involved in bonding.
Why does CF4 have a bond angle of 109.5 degrees?
As around the carbon there is 4 bonding pairs of electrons, so they repel equally and repel as far apart as possible.
How do you deduce the shape and angle of PF3?
P has 5 outer electrons and 3 in the 3 fluorine atoms.
This means 3 bonding and 1 lone pair.
Lone pairs repel more than bonding so its a trigonal pyramidal with an angle of 107 degrees.
Why cant the electron repulsion theory be used to determine shape of [CoCl4]2- ion?
As too many electrons in d orbitals
What element in period 3 has the highest mp?
Silicon as strong covalent bonds that require lots of energy to overcome.
What element in period 3 has the highest 1st ionisation energy?
Argon as highest nuclear charge and same amount of shielding so requires more energy to overcome.
2,2 
Bent
104.5
Suggest a value for the H-O-O bond in H2O2?
95 degrees
Why is the bp of H2S2 lower than H2O2?
As electronegativity in S is lower than in O and there is no hydrogen bonding in the H2S2 molecule
Suggest why the mp is high in ionic bonding?
As the oppositely charged ions have great attraction.
Whats the bond formed in an AlCl4- ion?
Dative as electron pair on Cl- is donated to Al.
Negative ion donates electron in dative bond.
Positive ion receives electrons in dative bond.