2.2

Question 1

What is Covalent bonding?

Answer 1

Electrostatic attraction between the positive nuclei of the atoms and the shared pair of electrons.

Question 2

Dative covalent bond.

Answer 2

A bond that forms where both electrons are from the same atom.

Question 3

what’s VSEPR theory?

Answer 3

The theory that negative electrons in a pair will repel eachother as far as possible.

Question 4

What’s the name and angles for two elements joined to a middle one and three elements joined to a middle one.

Answer 4

2- linear (angle 180°)

3- trigonal planer (angle 120°)

Question 5

Name and angles for 4, 5 and 6 elements joined to a central one.

Answer 5

4- tetrahedral (109.5°)

5- Trigonal bipyramidal (90° and 120°)

6- Octahedral (90°)

Question 6

What’s a bent/ non-linear compound.

Answer 6

When there are lone pairs the electrons are drawn closer to the nucleus than the bonding pairs. the angles change by 2.5° each time.

Question 7

What are Polar molecules?

Answer 7

When some electrons in a covalent bond have stronger attraction for electrons due to a greater electronegativity so one side is slight + or -

Question 8

when do the dipoles cancel?

Answer 8

When the molecule is symmetrical

Question 9

what are the different orbitals

Answer 9

s orbital- spherical (one orbital per level)

p orbital- dumbbell shape 90° to eachother (three orbitals per level)

d orbital- (five d orbitals per level)

Question 10

what are the properties of ionic bonding?

Answer 10

soluble in water- the ionic compounds that carry higher charges on the ions tend to be less soluble as it’s more energy to break

hard and brittle- if they are shifted a small amount it would move one layer of ions causing repulsion

crystalline solids with high melting points

conducts electricity when molten

Question 11

permeant dipole dipole bonds

Answer 11

molecules with permeant dipole will be attracted to other molecules with a permeant dipole as oppositely charged ions attract.

Question 12

induced or temporary dipole dipole attraction

Answer 12

uneven electron position

creates a temporary dipole

which induces a neighbouring molecule

Question 13

hydrogen bonding

Answer 13

bonding between molecules with N, O and F.

the hydrogen forms a bing with the lone pair of another molecule due to the dipoles

Question 14

how does hydrogen bonds have an impact on water.

Answer 14

ice is less dense due to the open lattice like structure.

Water has a higher boiling point compared to similar molecules of the same size as hydrogen bonds take a lot of energy to break.

Question 15

What is a sub shell?

Answer 15

An electron shell is made up of orbitals with the same principal quantum number.
With each shell orbitals are grouped together in a sub shell.
There are s,p,d and f orbitals.

Question 16

What is ionic bonding?

Answer 16

Electrostatic attraction between positive and negative ions.

Question 17

Properties of simple molecular structures.

Answer 17

Melting and Boiling points- low melting and bp because the intermolecular forces are weak so a small amount is needed to break them.

Electrical conductivity- non conductors.

Solubility- soluble in non polar solvents like hexane. weak temporary dipole forces are able to form between covalent molecules and these solvents.

Question 18

Giant covalent properties.

Answer 18

Melting and Boiling points- high melting and boiling.

Electrical conductivity- non conductors apart from graphite due to delocalised electrons between layers.

Solubility- insoluble in both polar and non polar solvents as the covalent bonds are too strong to break.