Manipal MET2018ChemistryRedox Reactions
In the standardization of Na ₂ ~S ₂ O ₃ using K ₂ Cr ₂ O ₇ by iodometry, the equivalent weight of K ₂ Cr ₂ O ₇ is
Options
- Amolecular weight/2
- Bmolecular weight/6
- Cmolecular weight/3
- Dsame as molecular weight
Correct answer
B. molecular weight/6
Step-by-step solution
Potassium dichromate acts like an oxidising agent in the presence of dilute H ₂ SO ₄ as: Cr ₂ O ₇ ²⁻+14 H ⁺+6 e⁻ 2 Cr ³⁺+7 H ₂ O Equivalent mass of K ₂ Cr ₂ O ₇= molecular mass of K ₂ Cr ₂ O ₇ 6