Reactions of metals with water
3 marks · EasyThe table shows some metals and their reactions with water or steam:
| Metal | Reacts with cold water? | Reacts with steam? |
|---|---|---|
| Potassium | Yes | No |
| Calcium | Yes | No |
| Magnesium | No | Yes |
| Copper | No | No |
Identify one metal from the table that reacts only with steam but not with cold water.
State the general word equation for the reaction of this metal with steam.
Name the gas produced in this reaction.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
(a) Magnesium · must show Magnesium
(b) metal + steam → metal oxide + hydrogen · must show General steam equation
(c) Hydrogen · must show Hydrogen
Common mistakes: Misreading table; giving cold water equation for steam; naming oxygen as product.
Show mark scheme and worked solution
Marking points
B1 (a) · 1 mark · Identifies magnesium as the only metal in the table that reacts with steam but not cold water.
B2 (b) · 1 mark · States correct general word equation: metal + steam → metal oxide + hydrogen.
B3 (c) · 1 mark · Names the gas produced as hydrogen.
Worked solution
a) Magnesium is the metal that reacts only with steam.
b) The general word equation is:
c) The gas produced is hydrogen.