Bonding

Question 1

Name the different types of intramolecular bonds and the type of elements they can be bonded to

Answer 1

Metallic (metals only)
Ionic (metals and non-metals)
Covalent (non-metals only)

Question 2

Properties of metallic bonding

Answer 2

Conductive
Ductile
Malleable
High melting and boiling points

Question 3

Structure of metallic bonding

Answer 3

Lattice structure where electrons are delocalised forming a sea of electrons

Question 4

Structure of an Ionic Bond

Answer 4

Electrostatic attraction between positive and negative ions in a lattice structure
Metal loses an electron
Non-metal gains an electron

Question 5

Properties of ionic bonding

Answer 5

High melting point
Solid at room temperature
Conducts electricity when molten or dissolved in water
Brittle —> because they form a lattice of alternating positive and negative ions

Question 6

Formula for sulfate

Answer 6

SO4 ^2-

Question 7

Formula for Hydroxide

Answer 7

OH-

Question 8

Formula for nitrate

Answer 8

NO3 ^-

Question 9

Formula for carbonate

Answer 9

CO3 ^2-

Question 10

Formula for ammonium

Answer 10

NH4 ^+

Question 11

Trends in metallic bonding

Answer 11

The greater the charge on the positive ion, the stronger the attractive force
Ions that are larger in size, produce a weaker attraction due to size

Question 12

Types of intermolecular bonds

Answer 12

Hydrogen bonds
Dipole - Dipole
Van Der Waals

Question 13

How are covalent bonds formed?

Answer 13

When orbitals, each containing 1 electron overlaps

Question 14

What is dative covalent bond?

Answer 14

This is when a bond contains a shared pair of electrons with both electrons provided by one atom

Question 15

Trends in Van Der Waals force

Answer 15

Larger the Mr of the molecule, the stronger the intermolecular forces

Question 16

Trends in Van Der Waals (hint: chains)

Answer 16

Straight chain molecules experience stronger van Der Waals forces than branched chain molecules
—>because they line up and pack close together
—>this reduces the distance over which the force acts

Question 17

Strongest intermolecular force?

Answer 17

Hydrogen bonding

Question 18

Weakest intermolecular force?

Answer 18

Van Der Waals

Question 19

What is a dipole-dipole force?

Answer 19

Acts between molecules with a polar bond

The + and - regions attract each other and hold the molecules together in a lattice-like structure

Question 20

Explain Hydrogen bonding

Answer 20

Forms between hydrogen and 3 most electronegative atoms: nitrogen, oxygen and fluorine.

Question 21

Properties of hydrogen bonding

Answer 21

Much higher melting and boiling points

Question 22

Explain when a Van Der Waals force can be strong

Answer 22

When the Mr is high or when the number of electrons are high

—> this means higher melting and boiling points

Question 23

What is VSEPR?

Answer 23

It shows how pairs of electrons in the outer shell repel each other and shows the shape of molecules

Question 24

Shape with 3 electrons

Answer 24

Triganol Planar (120°)

Question 25

Shape with 4 electrons

Answer 25

Tetrahedral (109.5°)

Question 26

Shape with 5 electrons

Answer 26

Trigonal Bipyramidal (90° and 120°)

Question 27

Shape with 6 electrons

Answer 27

Octahedral (90°)

Question 28

Shape with 2 electrons

Answer 28

Linear (180°)

Question 29

Characteristics of lone pairs of electrons

Answer 29

More repulsive than bonding pairs of electrons | —> this increases the bond angle

Question 30

Formula for pairs of electrons?

Answer 30

``` Pairs of e- = group no of central atom + no of bonded atoms +- charge -1 if positive +1 if negative -1 if double bond -2 if triple bond ```

Question 31

What is electronegativity?

Answer 31

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