Hydrogen And Water

Question 1

Metals react similarly to both

Answer 1

Dilute hydrochloric acid and dilute sulphuric acid

Question 2

Magnesium reacts to dilute HCl with…

Answer 2

Rapid fizzing, the mixture gets very hot, colourless magnesium sulphate / chloride solution forms

Question 3

Aluminium reacts with dilute HCL…

Answer 3

Slowly due to a coat of aluminium oxide. On heating this layer is removed and the aluminium fizzes a little like Mg

Question 4

Zinc reacts with dilute HCl…

Answer 4

Slowly with cold dilute acid and may produce some effervescence. However it fizzes more on heating

Question 5

Iron reacts with dilute HCl…

Answer 5

Slowly with cold dilute acid and will produce a bit of effervescence when heated

Question 6

When hydrogen combusts

Answer 6

Bonds are broken in the hydrogen and oxygen molecules, which form new bonds if water molecules

Question 7

The combustion of hydrogen is…

Answer 7

Exothermic and gives out water in the form of steam before it condenses into a liquid

Question 8

The equation for the combustion of hydrogen is…

Answer 8

2H2(g) + O2(g) = 2H2O(l)

Question 9

You test for water by…

Answer 9

Water turns anhydrous copper (II) sulphate blue

Turns cobalt chloride paper pink

Question 10

Equation for water reacting which anhydrous copper sulphate

Answer 10

CuSO4(s) + 5H2O(l) = CuSO4•5H2O

Question 11

You can check the purity of water by…

Answer 11

Checking it boils and freezes at the correct temperatures