CIE iGCSE Co-Ordinated Science C9.4 Reactivity series Exam Style Questions Paper 1
▶️ Answer/Explanation
The reactivity series from most reactive to least reactive is: potassium > sodium > calcium > magnesium > aluminium > carbon > zinc > iron > hydrogen > copper > silver > gold. Among the metals listed in the options, the correct order is potassium (most reactive), then calcium, then zinc, and finally copper (least reactive). Therefore, row C correctly shows this order.
✅ Answer: (C)
✅ Answer: (C)
▶️ Answer/Explanation
A reactive metal reacting with a dilute acid always produces a salt plus hydrogen gas.
Here magnesium reacts with hydrochloric acid to give the salt magnesium chloride and hydrogen gas, with no carbon-containing or extra water product.
The word equation is \(\text{magnesium} + \text{hydrochloric acid} \rightarrow \text{magnesium chloride} + \text{hydrogen}\).
✅ Answer: (A)
Here magnesium reacts with hydrochloric acid to give the salt magnesium chloride and hydrogen gas, with no carbon-containing or extra water product.
The word equation is \(\text{magnesium} + \text{hydrochloric acid} \rightarrow \text{magnesium chloride} + \text{hydrogen}\).
✅ Answer: (A)
▶️ Answer/Explanation
A metal can be extracted by heating its ore with carbon only if carbon is more reactive than that metal.
Carbon is more reactive than copper, so it can displace copper from its oxide, reducing it to the metal.
Its group position or bonding structure is not the reason it works for this extraction.
✅ Answer: (B)
Carbon is more reactive than copper, so it can displace copper from its oxide, reducing it to the metal.
Its group position or bonding structure is not the reason it works for this extraction.
✅ Answer: (B)
▶️ Answer/Explanation
A more reactive metal produces bubbles of hydrogen gas more vigorously and quickly with dilute acid.
Vigorous bubbling (metal 3) shows the most reactive metal, followed by steady bubbling (metal 4), then slow bubbling (metal 1), and no reaction (metal 2) shows the least reactive metal.
This gives the reactivity order 3 → 4 → 1 → 2.
✅ Answer: (D)
Vigorous bubbling (metal 3) shows the most reactive metal, followed by steady bubbling (metal 4), then slow bubbling (metal 1), and no reaction (metal 2) shows the least reactive metal.
This gives the reactivity order 3 → 4 → 1 → 2.
✅ Answer: (D)
▶️ Answer/Explanation
A metal that reacts with cold water is more reactive than one that only reacts with dilute hydrochloric acid.
A metal that produces hydrogen gas with neither water nor acid is the least reactive of the three.
Ranking the metals by how readily each releases hydrogen from water then acid gives the reactivity order Y, most reactive, followed by X, then Z, least reactive.
✅ Answer: (B)
A metal that produces hydrogen gas with neither water nor acid is the least reactive of the three.
Ranking the metals by how readily each releases hydrogen from water then acid gives the reactivity order Y, most reactive, followed by X, then Z, least reactive.
✅ Answer: (B)