C2.3 - Metals and Acids

Question 1

metal + hydrochloric acid → ?
metal + sulfuric acid → ?
metal + nitric acid → ?

Answer 1

metal chloride + hydrogen
metal sulfate + hydrogen
metal nitrate + hydrogen

Question 2

How do you test for hydrogen?

Answer 2

1) Collect the gas in an empty test tube above the reaction tube (where you have done the experiment)
2) Light a splint
3) Put the splint in the test tube that contains the gas
4) If there is a squeaky pop, it is hydrogen

https://www.youtube.com/watch?v=_GqBl83Koig Watch up to 0:57

Question 3

Write state symbols for these equations:
2Mg + O₂ → 2MgO
2Zn + O₂ → 2ZnO
2Fe + O₂ → 2FeO

Answer 3

2Mg₍ₛ₎ + O₂₍₉₎ → 2MgO₍ₛ₎
2Zn₍ₛ₎ + O₂₍₉₎ → 2ZnO₍ₛ₎
2Fe₍ₛ₎ + O₂₍₉₎ → 2FeO₍ₛ₎

(s) - Solid
(g) - Gas
(l) - Liquid

Note: Not required for this test
(aq) - aqueous solution (dissolved in water)

Question 4

Balance these equations:
Zn + O₂ → ZnO
Fe + Cl₂ → FeCl₃

Step by step guide:
https://www.bbc.co.uk/bitesize/guides/zg6bmsg/revision/3

Answer 4

2Zn + O₂ → 2ZnO
2Fe + 3Cl₂ → 2FeCl₃

Balancer:
https://www.webqc.org/balance.php

Question 5

What group reacts most vigorously with water?

Answer 5

Group 1: Alkali metals

Question 6

Solve this word equation:
Sodium + Water → ?

Note: this is a group 1 element so it reacts differently to others

Answer 6

Sodium + Water → Sodium hydroxide + hydrogen

Question 7

Balance, solve and add state symbols:
Na + H₂O → ?

Note: this is a group 1 element so it reacts differently to others

Answer 7

2Na₍ₛ₎ + 2H₂O₍ₗ₎ → 2NaOH₂₍aq₎ + H₂₍g₎

Question 8

How can you remember the reactivity series?
Potassium
Sodium
Calcium
Magnesium
Aluminium
Zinc
Iron
Copper
Silver
Gold

Answer 8

Please Stop Calling My Amazing Zebra In Class, She Grunts

Question 9

Name the elements in the reactivity series

Answer 9

Potassium
Sodium
Calcium
Magnesium
Aluminium
Zinc
Iron
Copper
Silver
Gold

Question 10

Metals with steam:

Mg(s) + H₂O(g) → ?

Answer 10

MgO(s) + H₂(g)

Magnesium oxide + hydrogen

Question 11

What is displacement?

Answer 11

Displacement is when a more reactive element displaces, or pushes out, a less reactive element from its compound.

Question 12

1) iron + copper sulfate → ?
2) magnesium + aluminium chloride→ ?
3) gold + copper oxide → ?

Answer 12

1) iron sulfate + copper
2) magnesium chloride + aluminium
3) no reaction

Question 13

What is the difference between an exothermic reaction and an endothermic reaction?

Answer 13

Exothermic - energy is transferred to the surroundings, the temperature of the surroundings increases
Endothermic - energy is taken from the surroundings, the temperature of the surroundings decrease

https://www.bbc.co.uk/bitesize/guides/z2b2k2p/revision/1#:~:text=When%20a%20chemical%20reaction%20happens,many%20oxidation%20reactions

Question 14

How is a thermite reaction created?

Answer 14

iron oxide + aluminium → iron + aluminium oxide
2Al(s) + Fe₂O₃(s) → Al₂O₃(s) + 2Fe(l)

The reaction is exothermic so the iron melts

Question 15

What is an ore?

Answer 15

An ore is a metal combined with another element to form a compound.

Question 16

How are metals extracted from ores?

Answer 16

1) Separate the metal from the compound it is mixed with

2) Use chemical reactions to extract the metal

Question 17

What non metal can be used to displace some metals from their ores?

Answer 17

Carbon

Question 18

What process is used when the metal you need to extract from an ore is more reactive than carbon?

Answer 18

Electrolysis:

Positively charged aluminium ions gain electrons from the cathode, and form molten aluminium
Oxide ions lose electrons at the anode, and form oxygen molecules (idk wth this means, you don’t need to know it)

Question 19

What are four properties of ceramics?

Answer 19

Physical Properties:
Hard - can only be scratched by harder materials (search up Moh scale)
Brittle - break easily
Stiff - difficult to bend
Solid at room temperature
Strong when forces press on them
Break easily when stretched
Electrical insulators
High melting points

Chemical Properties:
Do not react with water, acids or alkalis

Question 20

What is a polymer?

Answer 20

A substance with very long molecules.

Question 21

Name three examples for both synthetic and natural polymers.

Answer 21

Synthetic:
nylon - very strong, elastic and does not absorb water
polystyrene
poly(vinyl chloride) (PVC) - third most used type of plastic
polyethylene - most used type of plastic

Natural:
Wool
Cotton
Rubber

Question 22

What is a composite?

Answer 22

A composite is a mixture made of different materials to take advantage of both of their properties.

Question 23

Give an example of a composite.

Answer 23

Carbon-fiber-reinforced plastic - made from carbon fibres and a gluelike synthetic polymer.
Reinforced concrete - has a steel bar through the middle and has concrete around the sides.
Glass-fibre-reinforced aluminium - made from thin layers of aluminium, layers of glass fibre and a gluelike polymer to join the layers.