Chemistry - The Reactivity Series

Question 1

What is the reactivity series?

Answer 1

Potassium > Sodium > Calcium > Aluminium > Carbon > Zinc > Iron > Lead > Hydrogen > Copper > Silver > Gold

Question 2

How can the order of reactivity be determined?

Answer 2

• Cold water
• Steam
• Dilute hydrochloric acid

Question 3

What are the characteristics of reaction of metals with cold water?

Answer 3

• Only reacts with some metals
• Most reactive metals react violently with cold water
  Metal + water –> metal hydroxide + hydrogen

Question 4

What are the reactions of metals with cold water?

Answer 4

Potassium: very violent
Sodium: violent
Calcium: reacts readily
Magnesium: very slowly
Zinc, iron, lead, copper, silver: unreactive (except rusting for iron)

Question 5

What are the characteristics of reaction of metals with steam?

Answer 5

• moderately reactive metals like zinc and iron react with steam instead of cold water
• metal + steam –> metal oxide + hydrogen

Question 6

What are the reactions of metals with steam?

Answer 6

Potassium, sodium, calcium: reacts violently
HOT magnesium: reacts violently, bright white glow produced
HOT zinc: reacts readily, produced zinc oxide which is yellow when hot and white when cold (the only metal that will change in colour)
RED-HOT iron: reacts slowly, must be constantly heated
Lead, copper, silver, gold: no reaction

Question 7

What are the characteristics of reaction of metals with dilute hydrochloric acid?

Answer 7

• Metals above hydrogen (excluding LEAD) react with dilute hydrochloric acid to produce hydrogen gas
  Metal + HCL –> metal chloride + hydrogen

Question 8

What are the reactions of metals with dilute hydrochloric acid?

Answer 8

Potassium, sodium: reacts explosively
Calcium: reacts violently
Magnesium: reacts rapidly
Zinc: reacts moderately fast
Iron: reacts slowly
Lead, copper, silver: no reaction occurs

Question 9

Why does no reaction occur with lead and the 3 reactants?

Answer 9

During the reaction, an insoluble layer of lead(II) chloride is formed, which coats the lead and prevents further reaction.

Question 10

What are the characteristics of reaction of metal oxides with carbon?

Answer 10

• carbon is the reducing agent
• only metals below carbon in the reactivity series can be reduced by carbon
• oxide of zinc would require the highest temperature

Question 11

What are the characteristics of reaction of metal oxides with hydrogen?

Answer 11

• will reduce the oxide of metals from IRON AND BELOW
• iron(II) oxide would require the highest temperature

Question 12

How does reactivity of metals affect the tendency to form positive ions?

Answer 12

• The lower the metal is in the reactivity series → the likelier the metal oxide can be reduced
• The more reactive a metal is, the easier it is to be oxidised → greater tendency to form positive ions (lose electrons more readily).

Question 13

What is the action of heat on metal carbonates?

Answer 13

Some metal carbonates can be decomposed by heat to produce carbon dioxide. The more reactive a metal is → more difficult to decompose its carbonate by heat

Question 14

What are the reactions of action of heat on metal carbonates?

Answer 14

Potassium, sodium carbonates: unaffected by heat (stable to heat)
Calcium, magnesium, zinc, iron, lead, copper carbonates: decompose into metal oxide and carbon dioxide upon heating
Silver carbonate: decomposes into silver and carbon dioxide upon heating (the silver oxide produced is thermally unstable and further decomposes into silver)