Making predictions using the reactivity series
4 marks · NormalA student investigates the reactions of five metals with dilute hydrochloric acid at room temperature.
| Metal | Observation with dilute HCl |
|---|---|
| Sodium | Fizzes rapidly, dissolves |
| Magnesium | Slow bubbles, dissolves gradually |
| Iron | Very slow bubbles, little change |
| Copper | No reaction |
| Calcium | Bubbles rapidly, cloudy solution |
Arrange the five metals in order of decreasing reactivity with dilute hydrochloric acid (most to least reactive).
Predict whether magnesium will react with steam. Give a reason for your answer.
Suggest, with a reason, if copper will react with silver nitrate solution.
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) Sodium, calcium, magnesium, iron, copper
(b) Yes; magnesium is above hydrogen and reacts with steam to form magnesium oxide and hydrogen.
(c) No; copper is below silver in the reactivity series, so it cannot displace silver from silver nitrate solution. · must show Comparing positions of copper and silver, Correct explanation
Common mistakes: Reversing the order; Assuming all metals react the same
Show mark scheme and worked solution
Marking points
B1 (a) · 1 mark · Correct sequence: sodium > calcium > magnesium > iron > copper
B2 (b) · 1 mark · States magnesium will react with steam and gives correct reasoning.
B3 (c) · 1 mark · States copper will not react with silver nitrate solution.
B4 (c) · 1 mark · Gives correct reason referencing copper and silver's positions in the series.
Worked solution
a) Reactivity: sodium (most vigorous), calcium, magnesium, iron, copper (no reaction).
Order: sodium > calcium > magnesium > iron > copper
b) Magnesium will react with steam because it is above hydrogen.
c) Copper is below silver in the reactivity series, so it cannot displace silver from its nitrate solution.