Topic 9: Metals

Question 1

Are metals good conductors of heat and electricity?

Answer 1

Yes, they are.

Question 2

Are non-metals good conductors of electricity?

Answer 2

No, except for graphite.

Question 3

What does malleable mean?

Answer 3

Can be hammered into shapes.

Question 4

What does ductile mean?

Answer 4

Can be drawn into wires.

Question 5

Do metals have high or low melting points?

Answer 5

High melting points.

Question 6

Are non-metals brittle or strong?

Answer 6

Brittle.

Question 7

What happens when a metal reacts with acid?

Answer 7

Metal + Acid → Salt + Hydrogen

Question 8

What happens when metal reacts with water?

Answer 8

Metal + Water → Metal Hydroxide + Hydrogen

Question 9

What happens when metal reacts with steam?

Answer 9

Metal + Steam → Metal Oxide + Hydrogen

Question 10

Why is aluminium used in aircraft?

Answer 10

Low density.

Question 11

Why is aluminium used in cables?

Answer 11

Low density and good conductor.

Question 12

Why is aluminium used in food containers?

Answer 12

It resists corrosion.

Question 13

Why is copper used in wires?

Answer 13

It conducts electricity well and is ductile.

Question 14

What is an alloy?

Answer 14

A mixture of a metal with other elements.

Question 15

What are alloys harder than?

Answer 15

Pure metals.

Question 16

What is brass made of?

Answer 16

Copper and zinc.

Question 17

What is stainless steel made of?

Answer 17

Iron, carbon, chromium, and nickel.

Question 18

Why are alloys stronger?

Answer 18

Mixed atom sizes stop layers from sliding.

Question 19

What is the reactivity series?

Answer 19

K, Na, Ca, Mg, Al, C, Zn, Fe, H, Cu, Ag, Au

Question 20

Which metals react with cold water?

Answer 20

Potassium, sodium, calcium.

Question 21

Which metal reacts with steam?

Answer 21

Magnesium.

Question 22

Which metals do NOT react with acid?

Answer 22

Copper, silver, gold.

Question 23

What is a displacement reaction?

Answer 23

A more reactive metal replaces a less reactive one.

Question 24

What causes rusting?

Answer 24

Water and oxygen.

Question 25

What is rust?

Answer 25

Hydrated iron(III) oxide.

Question 26

What are barrier methods?

Answer 26

Paint, grease, or plastic coating.

Question 27

What is galvanising?

Answer 27

Coating iron with zinc.

Question 28

What is sacrificial protection?

Answer 28

A more reactive metal corrodes instead of iron.

Question 29

What is the main ore of aluminium?

Answer 29

Bauxite.

Question 30

How is aluminium extracted?

Answer 30

Electrolysis.

Question 31

Why use molten cryolite in aluminium extraction?

Answer 31

Lowers melting point and improves conductivity.

Question 32

What is the ore of iron?

Answer 32

Haematite (Fe₂O₃).

Question 33

What reduces iron in the blast furnace?

Answer 33

Carbon monoxide.

Question 34

What makes metals good conductors of electricity?

Answer 34

They have free-moving delocalised electrons.

Question 35

Why are alloys harder than pure metals?

Answer 35

Different-sized atoms disrupt the layers, making it harder for them to slide over each other.

Question 36

Which metal is a liquid at room temperature?

Answer 36

Mercury.

Question 37

What are the two conditions for rusting?

Answer 37

Oxygen and water.

Question 38

What is sacrificial protection?

Answer 38

A more reactive metal (like zinc) corrodes instead of iron.

Question 39

Why does zinc protect iron in galvanising?

Answer 39

It acts as both a barrier and a sacrificial metal.

Question 40

What is slag made of in the blast furnace?

Answer 40

Calcium silicate (CaSiO₃).

Question 41

What happens in a displacement reaction?

Answer 41

A more reactive metal replaces a less reactive metal from its compound.

Question 42

Which gas is always formed when a reactive metal reacts with acid or water?

Answer 42

Hydrogen gas.