Metals

Question 1

Describe these properties for metals and non metals:

1) appearance
2) electrical conduction
3) density
4) melting point
5) flexibility

Answer 1

1) shiny
dull

2) good conductors
poor conductors (but graphene conducts electricity)

3) high
low

4) high (but mercury is liquid at room temp)
low (but diamond/graphene have high melting points)

5) malleable
brittle

Question 2

define malleable and brittle

Answer 2

can be pressed into shape without shattering

shatter when bent or hit

Question 3

Describe metallic structure

Answer 3

• giant lattice of positively charged metal ions

- ‘sea’ of delocalised electrons (negative charge) from outer shell of the atoms

Question 4

How is a metallic structure held together/what is a metallic bond?

Answer 4

strong electrostatic forces of attraction between positive metal ions and negative delocalised electrons

Question 5

properties of metallic bonding

Answer 5

conducts electricity

conducts thermal energy

malleable

Question 6

Why are metals malleable?

Answer 6

if a force is applied:

• layers of positive ions slide over each other
• metal changes shape without shattering

Question 7

Describe and explain the (in)solubility of metals

Answer 7

most metals are insoluble in water
some are soluble

• they react with water to form soluble metal hydroxides
• these dissolve and expose more metal to the water

(sodium reacts with water to form sodium hydroxide solution and hydrogen)

Question 8

Copper is used in electricity cables

Explain, in terms of structure and bonding, why metals are good conductors of electricity

Answer 8

metals contain delocalised electrons which can move through the structure of the metal and carry electrical charge

Question 9

Aluminium is used to make overhead mains electricity cables

Explain in terms of structure and bonding why aluminium is:

1) ductile
2) a good conductor of electricity

Answer 9

1) layers of positive ions/atoms can slide over each other

2) delocalised electrons can move through the structure and carry electrical charge

Question 10

ductile

Answer 10

can be pulled without breaking

Question 11

Mercury is a liquid metal at room temperature

State whether it should conduct electricity, giving a reason for your answer

Answer 11

it should conduct electricity because it has delocalised electrons that can move and carry electrical charge