Exams › JEE Main › Chemistry

Which statement(s) about Cr(2+) and Mn(3+) is/are correct? (Atomic numbers: Cr = 24, Mn = 25)

1. Only Cr2+ is a reducing agent
2. Cr2+ is a reducing agent, Mn3+ is an oxidising agent, both are d4, and Cr2+ on acting as reductant becomes d3
3. Both Cr2+ and Mn3+ are reducing agents
4. Mn3+ is a reducing agent and Cr2+ is an oxidising agent

Correct answer: Cr2+ is a reducing agent, Mn3+ is an oxidising agent, both are d4, and Cr2+ on acting as reductant becomes d3

Solution

Cr2+ (d4) is a reducing agent because Cr3+ (d3, stable t2g³) forms; Mn3+ (d4) is an oxidising agent because reduction to Mn2+ gives stable d5. Both ions are d4.

Related JEE Main Chemistry questions

• A transition metal M gives a volatile chloride whose vapour density is 94.8. If this chloride contains 74.75% chlorine by mass, what is the formula of the metal chloride?
• What is the ratio of the magnetic moments of Fe(III) and Co(II)?
• Which of the following species contains the greatest number of unpaired electrons?
• Which of the following species contains an atom in the +6 oxidation state?
• Which of the following pairs contains compounds in which the metal in each case is present in its maximum possible oxidation state?
• Among the following metal oxides, which one exhibits antiferromagnetic behavior?

⚔️ Practice JEE Main Chemistry free + battle 1v1 →