Bonding And Structure

Question 1

What is ionic bonding between

Answer 1

Metal atoms and non-metal atoms

Question 2

Using full electronic structures, explain the bonding in potassium sulfide

Answer 2

The 2 potassium atoms (2.8.8.1) gives their outer shell electrons to the sulphur atom (2.6). The potassium atom now (2.8.8) becomes positively charged and the sulphur atom now (2.8) becomes negatively charged (2-)

Question 3

3 physical properties of ionic substances

Answer 3

• high melting and boiling points
• conduct electricity when molten or dissolved in water but not when solid
• soluble in water (because water is a polar solvent).

Question 4

What is covalent bonding between

Answer 4

Tow non-metal atoms share a pair of electrons

Question 5

What is a bonding pair

Answer 5

Two electrons shared in the bond

Question 6

What is lone pairs

Answer 6

Any pairs of electrons that are not in the molecule

Question 7

What is a molecule

Answer 7

Two or more atoms covalently bonded

Question 8

Diatomic meaning

Answer 8

When only two atoms are covalently bonded in the molecule it is described as being diatomic

Question 9

3 substances that have multiple covalent bonds, and state how many bonds that have

Answer 9

• nitrogen, 3
• oxygen, 2
• CO2, o=c=o

Question 10

The weak forces holding molecules together

Answer 10

Van der waals

Question 11

What do van der waals increase with

Answer 11

Relative molecules mass

Question 12

3 properties of molecular covalent substances

Answer 12

• low melting points and boiling points, it does not take much heat energy to overcome the weak forces of attraction (van der waals).
• they usually do not dissolve well in water (insoluble) but do dissolve in non-polar solvents
• they do not conduct electricity

Question 13

What are allotropes

Answer 13

Different forms of the same element that exist in the same physical state

Question 14

What does the structure in a metal consist of

Answer 14

Layers of regularly arranged metal cations with delocalised electrons

Question 15

3 properties of metals

Answer 15

• high melting points
• malleable
• conduct electricity

Question 16

1 use of a) aluminium b) copper c) iron d) magnesium

Answer 16

A) saucepans
B) water pipes
C) bridges
D) flares

Question 17

What is an alloy

Answer 17

A mixture of two or more elements, at-least one of which is a metal

Question 18

Why are alloys harder

Answer 18

They contain atoms of different sizes, which distort the regular arrangements of atoms. This makes it more difficult for the layers to slide over each other, so alloys are harder than the pure metal but still retain the properties of a metal

Question 19

How do you work out the percentage of gold in karats, e.g. 18 karats

Answer 19

(18 divided 24) x 100 = percentage of gold

Question 20

How are metals able to conduct electricity

Answer 20

The delocalised electrons are able to carry charge