U3-2 - Metals

Question 1

Elements from a group in the periodic table all react with water.

Name this group.

Answer 1

Alkali metals (group 1)

Question 2

Calcium reacts with water and acids to produce a gas.

Name this gas.

Answer 2

Hydrogen

Question 3

Chemical test for hydrogen gas

Answer 3

Burns with a (squeaky) pop

Question 4

Metal + Acid → …….

Answer 4

Salt + Hydrogen

Question 5

Metal + Oxygen → ….

Answer 5

Metal oxide

Question 6

Metal + Water → ….

Answer 6

Metal hydroxide + Hydrogen

Question 7

Ores

Answer 7

Rocks containing metal compounds

Question 8

Very reactive metals (e.g. Na) must be extracted via ____.

Answer 8

electrolysis

Question 9

Unreactive metals can be extracted via _______.

Answer 9

heating alone

Question 10

Metals like iron can be extracted via _____.

Answer 10

heating with carbon

Question 11

Electrolysis

Answer 11

Breaking down a compound using electricity.

Question 12

Bronze, brass, steel

What type of substances are these?

Answer 12

Alloys

Question 13

Alloy

Answer 13

Solid mixture of two or more elements, at least one of which is a metal.

Question 14

Answer 14

Question 15

Answer 15

Question 16

Electrolyte

Answer 16

Electrically conducting solution containing ions, e.g. salt solution.

Question 17

Electrode

Answer 17

A solid conductor (metal or graphite).

Question 18

Which non-metal can be used for electrodes?

Answer 18

Graphite

Question 19

Electricity passes through metal wires as a flow of _______.

Answer 19

electrons

Question 20

Electricity passes through an electrolyte solution as a flow of _______.

Answer 20

ions

Question 21

What is the direction of electron flow in electrochemical cells?

Answer 21

From the metal higher in the electrochemical series to the one lower

(if you look at the ECS, e^– flow down)

Question 22

Metals far apart in the ECS produce ________ voltages than metals close together.

Answer 22

higher

Question 23

Which pairs of metals produce higher voltages:

far apart in the ECS

close to each other in the ECS?

Answer 23

Metals far apart

Question 24

Corrosion

Answer 24

A chemical reaction in which the surface of a metal changes from an element to a compound.

Question 25

More _________ metals corrode faster.

Answer 25

reactive

Question 26

Rusting

Answer 26

Corrosion of iron and steel

Question 27

What is required for rusting to occur?

Answer 27

Oxygen and water

Question 28

During rusting, iron atoms change into _____.

Answer 28

iron ions

Question 29

Rust indicator

Answer 29

Ferroxyl

Question 30

Colour change of ferroxyl indicator

Answer 30

Yellow to blue (if iron ions present)

Question 31

What types of substances increase the rate of corrosion?

Answer 31

Salt solution, acid

Question 32

Name the two types of rust prevention.

Answer 32

Physical and electrochemical

Question 33

Electrochemical protection prevents rusting by __________.

Answer 33

providing iron with electrons

Question 34

Physical protection prevents rusting by _______.

Answer 34

keeping oxygen and water away from the metal surface

Question 35

When using sacrificial protection, you attach iron to _____.

Answer 35

a metal above iron in the ECS (e.g. Mg)

Question 36

How does sacrificial protection prevent rusting?

Answer 36

The metal attached to iron corrodes and gives its e⁻ to the iron.

(Iron only rusts if the other metal is fully corroded.)

Question 37

Give one example of a substance used for physical protection from rusting

Answer 37

Any one of:

paint, oil, wax, grease, plastic, zinc (galvanising)