◈ Oracle Prep Sign Up Free

A-LevelChemistryElectrochemistry9701/12 · May/June 2020 · Q51 Mark

In this question you should use changes in oxidation numbers to balance a chemical equation. The following reaction occurs when MnO2 is warmed with dilute H2SO4. a MnO2 + b H⁺ → c Mn²⁺ + d MnO4¯ + e H₂O What is the ratio of c : d in the correctly balanced equation?

A1:1

B1:2

C2:3

D3:2

✓ Correct answer

D: 3:2

Practise more questions on this topic

Oracle Prep sorts past-paper questions by topic, so you can drill Electrochemistry and see which topics are most likely to come up next.

Sign up free →

About this question

Topic: Electrochemistry, A-Level Chemistry (syllabus 9701). Multiple choice, 1 mark.
Source: A-Level Chemistry, May/June 2020 Paper 1 Variant 2, question 5.

Questions and mark schemes are from past examination papers and remain the copyright of the exam board. How Oracle Prep builds its content

Related Chemistry questions

ElectrochemistryFeb/Mar 20201m

In the redox reaction shown, how do the oxidation states of vanadium and sulfur change? VO2+ + SO2 → V3+ + SO42-

ElectrochemistryFeb/Mar 20201m

When the equation is correctly balanced, what is the value of c? aC2H4 + bH2O + cH+ + 2MnO4- → dC2H6O2 + eMn2+

ElectrochemistryFeb/Mar 20211m

When concentrated sulfuric acid reacts with sodium iodide the products include sulfur, iodine, hydrogen sulfide and s…

Carbonyl compoundsFeb/Mar 20171m

Diols in which both hydroxy groups are bonded to the same carbon can spontaneously eliminate a molecule of water to p…

Hydroxy compoundsFeb/Mar 20171m

Propan-2-ol undergoes many reactions. Which row is correct?

Carbonyl compoundsFeb/Mar 20171m

CH₃CH₂COCH₂CH₃ reacts with hydrogen cyanide to form an organic product called a cyanohydrin. Which statement is correct?

← Browse all past-paper questions