Bonding

Question 1

Ionic bonding

Answer 1

Involves electrostatic attraction between oppositely charged ions in a lattice

Question 2

Ionic formulas

Answer 2

Positive cation-metal, no name change

Negative anion-non metal, name change

Question 3

Metallic bonding

Answer 3

Involves attraction between delocalised electrons and positive ions arranged in a lattice

Question 4

Metal properties

Answer 4

Good conductors-delocalised electrons

Strong, malleable, ductile, high melting points

Question 5

What does strength of metsllic bond depend on

Answer 5

The size and charge of the ion

Question 6

Covalent bonds

Answer 6

Metal and non metal react to share electrons and attain full outer shells
Nucleinof each atombattracted to shared electron pair

Question 7

What covalent bonds are strongest

Answer 7

1pair-longest and weakest

3 pairs-shortest and strongest

Question 8

Dative covalent bond

Answer 8

A covalent bond in which both ekectrons come from the same atom
- drawn with arrow in direction of electron movement not line

Question 9

How to work out shape of molecules

Answer 9

Central atom
Group/ outer electron number
Charge
Bonds
Total
Divide by 2=number of electron pairs
Structure
Look at 6 and 4 to wirk out lone pairs
Shape
Bond angle

Question 10

Pair repulsion theory

Answer 10

Outer shell electron pairs arrange as far apart as possible to minimise repulsion
Lone pair-lone pair=greatest repulsion
Bond pair-bond pair=least repulsion

Question 11

Form of electron pairs

Answer 11

As charge clouds that repel each other

Question 12

Molecular shapes

Answer 12

Linear-180•
Trigonal planar-120•
Tetrahedral-109.5
Trigonal bipyrimidal-120/90•
Octahedral-90•

Question 13

Electronegativity

Answer 13

The power of an atom to attract the pair of electrons in a covalent bond

Question 14

Electronegativity patterns

Answer 14

Increases accross period

Decreases down group

Question 15

Factors affecting electronegativity

Answer 15

Nuclear charge-more protons=stonger bp nucleus attraction
Atomic radius-closer bonding electrons,stronger attraction
Shielding-less shells shielding bp, sttonger force

Question 16

Polar covalent bonds

Answer 16

2 atoms in covalent bond have different electronegativity
2 electrons not shared equally
More e is d-, less e is d+

Question 17

Non polar covalent bond

Answer 17

2 atoms in covalent bond have same electronegativity

2 atoms shared equally

Question 18

Weakest to strongest IMF

Answer 18

Van der waals-weakest
Dipole dipole
Hydrogen-strongest

Question 19

VDW(induced dipole dipole)

Answer 19

More e at one end of atom by chance at 1 moment, w slight d-/+
This makes an instantaneous dipole and weak force of attraction between 2 neighbouring oppositely charged ends of temporary dipoles
Vdw always exist

Question 20

Dipole-dipole (permanent)

Answer 20

Bond between polar molecules, attractive force between dipoles on different molecules
Permanent so stronger than VDW

Question 21

Dipole moment

Answer 21

Some covalent bonds are polarso arramgenent can result in molecule iverall becoming polar

Question 22

Hydrogen bonding elements

Answer 22

Nitrogen
Oxygen
Fluorine

Question 23

Shape of covalent to H bond

Answer 23

Linear

Question 24

H bonds

Answer 24

H bonded to v electronegative atom
Strong intermolecular force not bond
Polar bond leaves H nucleus exposed as only one electron so strong attraction between exposed nucleus and lone pair on NOF

Question 25

Crystal structures

Answer 25

Ionic
Metallic
Giant covalent
Molecular

Question 26

Crystal structure examples

Answer 26

Diamond
Graphite
Ice
Iodine
Magnesium
Sodium chloride

Question 27

Clear ice explanation

Answer 27

Clear as light oasses through middle of hexagonal structure