Metals

Question 1

Reactions with cold water

Answer 1

Potassium, sodium, calcium—— reacts with cold water to produce hydroxides and hydrogen gas
Magnesium——-Reacts slowly with water
Zinc iron lead copper silver——- No reaction occurs

Question 2

Reaction with hot steam

Answer 2

Potassium, sodium calcium——— explosive reaction, dangerous to conduct
Magnesium——— reacts vigorously with steam
Zinc iron———— reacts with steam to produce oxides and hydrogen gas
Lead copper silver———- no reaction occurs

Question 3

Reactions with dilute hydrochloric acid

Answer 3

Potassium sodium calcium———explosive reaction, dangerous to conduct
Magnesium zinc iron———-reacts with dilute causes to produce salts and hydrogen gas
Lead——— only reacts slowly with an acid when heated
Copper silver———- no reaction occurs

Question 4

Heating with oxygen gas

Answer 4

Potassium sodium calcium———violent reaction, dangerous to conduct
Magnesium——— burns in oxygen with a bright white flame
Zinc iron lead copper——— reacts with oxygen in the presence of heat to produce oxides
Silver——-no reaction occurs

Question 5

Reduction with carbon

Answer 5

Potassium oxide, sodium oxide, calcium oxide, magnesium oxide——- oxides may not be reduced by heating with coke.
Zinc oxide, iron oxide, lead oxide, calcium oxide, silver oxide——- oxides reduced by heating with coke
Silver oxide can be reduced just by heating alone.

Question 6

Reduction with hydrogen

Answer 6

Potassium oxide, sodium oxide, calcium oxide, magnesium oxide, zinc oxide——- may not be reduced by heating with hydrogen
Iron oxide, lead oxide, calcium oxide, silver oxide—- may be reduced by heating with hydrogen

Question 7

Define recycling.

Answer 7

Recycling of metals refers to the collecting, sorting and melting down of scrap metal and putting them to new uses.

Question 8

Why is recycling important

Answer 8

Recycling is important as metals are a finite and resources and by recycling these finite resources, they can be sued gain for future use.