Question detail

Chemical changes case 111 reactivity-evidence. A student uses the reactivity series to justify an observation. Which option is best? Focus on why filtration used after reacting acid with excess in Soluble salts, not on a neighbouring Unit 4.4 reaction idea.

Try the question, check the answer, then read the explanation to understand the curriculum point.

Show answer Topic hub Objective page

At a glance

MCQ

Type

practice

Style

Topic

Reactions of acids

Question

A. Chemical changes case 111 reactivity-evidence: Uses the relative reactivity order to predict the change for why filtration used after reacting acid with excess
B. Chemical changes case 111 reactivity-evidence: Chooses the product by memorising a colour instead of the series (Soluble salts)
C. Chemical changes case 111 reactivity-evidence: Says any metal can displace any other metal ion (why filtration used after reacting acid with excess)
D. Chemical changes case 111 reactivity-evidence: Ignores whether the reacting substance is more or less reactive (Reactions of acids)

Answer

The correct option is Chemical changes case 111 reactivity-evidence: Uses the relative reactivity order to predict the change for why filtration used after reacting acid with excess.

Explanation

The correct option is Chemical changes case 111 reactivity-evidence: Uses the relative reactivity order to predict the change for why filtration used after reacting acid with excess. It is correct because it directly supports the approved learning objective to explain why filtration is used after reacting an acid with an excess insoluble solid in Soluble salts. The other options are incorrect because they blur a Unit 4.4 concept boundary: acid versus alkali versus base, oxidation versus reduction, displacement versus reduction, electrolysis versus electroplating, anode versus cathode, positive versus negative ions, oxidation state versus ionic charge, or strong acid versus concentrated acid.

Common mistake

Misunderstanding Filtration Purpose

Students often think that filtration is used to separate the acid from the insoluble solid instead of understanding that it is used to remove the excess insoluble solid from the solution.

Emphasize that filtration is specifically for separating the unreacted solid from the solution containing the soluble salt.

Related flashcards

Flashcard 1 of 5

Press Space to flip, arrows to move

For Soluble salts, which exam wording answer best supports this Unit 4.4 objective: Explain why filtration is used after reacting an acid with an excess insoluble solid?