Oxidation and Reduction

Chemistry ⇒ Redox Reactions and Electrochemistry

Oxidation and Reduction starts at 10 and continues till grade 12. QuestionsToday has an evolving set of questions to continuously challenge students so that their knowledge grows in Oxidation and Reduction. How you perform is determined by your score and the time you take. When you play a quiz, your answers are evaluated in concept instead of actual words and definitions used.

See sample questions for grade 12

Assign the oxidation number to chlorine in \mathrm{KClO_4}.

Assign the oxidation number to chromium in \mathrm{Cr_2O_7^{2-}}.

Assign the oxidation number to nitrogen in \mathrm{NH_4^+}.

Calculate the oxidation number of sulfur in \mathrm{Na_2S_2O_3}.

Describe the steps to balance a redox reaction using the ion-electron method.

Describe what happens to the oxidation number of an element when it is oxidized.

Explain the difference between an oxidizing agent and a reducing agent.

Explain the term 'auto-oxidation' with an example.

Explain why the reaction 2\mathrm{Fe^{3+}} + 2\mathrm{I^-} \rightarrow 2\mathrm{Fe^{2+}} + \mathrm{I_2} is a redox reaction.

Explain why the reaction between hydrogen and fluorine to form hydrogen fluoride is a redox reaction.

Identify the oxidizing agent in the following reaction: \mathrm{Zn} + \mathrm{CuSO_4} \rightarrow \mathrm{ZnSO_4} + \mathrm{Cu}

In the reaction: 2\mathrm{H_2O} + 2\mathrm{Na} \rightarrow 2\mathrm{NaOH} + \mathrm{H_2}, which element is oxidized?

State the change in oxidation number of chlorine in the reaction: \mathrm{Cl_2} + 2\mathrm{NaBr} \rightarrow 2\mathrm{NaCl} + \mathrm{Br_2}.

State the oxidation number of carbon in \mathrm{CO_2}.

State the oxidation number of chlorine in \mathrm{NaClO_3}.

Which species is reduced in the following reaction? 2\mathrm{Fe^{3+}} + 2\mathrm{I^-} \rightarrow 2\mathrm{Fe^{2+}} + \mathrm{I_2}