Question detail

Chemical changes case 149 ph-precision. A student explains pH or neutralisation. Which option avoids vague wording? Focus on reduction gain electrons in Oxidation and reduction in terms of electrons (HT only), not on a neighbouring Unit 4.4 reaction idea.

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

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At a glance

MCQ

Type

practice

Style

Topic

Reactivity of metals

Question

A. Chemical changes case 149 ph-precision: Links pH or neutralisation to hydrogen ions, hydroxide ions or water formation for reduction gain electrons
B. Chemical changes case 149 ph-precision: Says strong acid means concentrated acid (Oxidation and reduction in terms of electrons (HT only))
C. Chemical changes case 149 ph-precision: Says neutralisation only means the mixture becomes harmless (reduction gain electrons)
D. Chemical changes case 149 ph-precision: Uses pH numbers without linking them to acidity or alkalinity (Reactivity of metals)

Answer

The correct option is Chemical changes case 149 ph-precision: Links pH or neutralisation to hydrogen ions, hydroxide ions or water formation for reduction gain electrons.

Explanation

The correct option is Chemical changes case 149 ph-precision: Links pH or neutralisation to hydrogen ions, hydroxide ions or water formation for reduction gain electrons. It is correct because it directly supports the approved learning objective to (HT only) Define reduction as gain of electrons in Oxidation and reduction in terms of electrons (HT only). 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 Reduction

Students often confuse reduction with the addition of oxygen instead of the gain of electrons.

Remember that reduction specifically refers to the gain of electrons, while oxidation is the loss of electrons.

Related flashcards

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For Oxidation and reduction in terms of electrons (HT only), which acid-base focus answer best supports this Unit 4.4 objective: (HT only) Define reduction as gain of electrons?