Exams › JEE Main › Chemistry

In the unbalanced redox equation below, how many electrons are transferred overall? Cr2O7²− + Fe2+ + C2O4²− → Cr3+ + Fe3+ + CO2

1. 3
2. 4
3. 6
4. 5

Correct answer: 6

Solution

In this redox reaction, chromium is reduced from Cr2O7²− to Cr3+, which involves a transfer of 6 electrons, while iron is oxidized from Fe2+ to Fe3+, which involves a transfer of 1 electron. The overall electron transfer is determined by balancing the half-reactions, leading to a total of 6 electrons being transferred.

Related JEE Main Chemistry questions

• What volume of 20-volume hydrogen peroxide is needed to produce 5 L of oxygen gas at STP?
• Which one of the following reactions shows sulfuric acid acting as an oxidizing agent?
• Which of the following statements about redox behavior are true? (i) A metal M whose standard reduction potential for the half-reaction Mⁿ⁺ + ne⁻ ⇌ M is highly negative acts as a strong reducing agent. (ii) The oxidizing strength of the halogens falls in the order chlorine to iodine. (iii) The reducing strength of hydrogen halides rises from hydrogen chloride to hydrogen iodide.
• For the balanced redox equation X MnO4⁻ + Y C2O4²⁻ + Z H⁺ → X Mn²⁺ + 2Y CO2 + Z/2 H2O, what are the values of X, Y, and Z, respectively?
• Balance the redox equation below and identify the coefficients X, Y and Z in order: XNa2HAsO3 + YNaBrO3 + ZHCl → NaBr + H3AsO4 + NaCl
• Arrange the following sulphur-containing anions in order of increasing oxidation state of sulphur: SO3²⁻, S2O4²⁻ and S2O6²⁻.

⚔️ Practice JEE Main Chemistry free + battle 1v1 →