Q62 / 180 · AIIMS 2006 · Chemistry
Assertion : $\mathrm{K}_2 \mathrm{Cr}_2 \mathrm{O}_7$ is used as primary standard in volumetric analysis.
Reason : It has a good solubility in water.
- AIf both assertion and reason are true and reason is the correct explanation of the assertion
- BIf both assertion and reason are true but reason is not the correct explanation of the assertion
- Correct answerCIf assertion is true, but reason is false
- DBoth assertion and reason are false statements.
Solution
$\mathrm{K}_2 \mathrm{Cr}_2 \mathrm{O}_7$ is less soluble in water. $\mathrm{K}_2 \mathrm{Cr}_2 \mathrm{O}_7$ can be found in pure state and can be accurately weighed. It is not hygroscopic in nature. So $\mathrm{K}_2 \mathrm{Cr}_2 \mathrm{O}_7$ is used as a primary standard solution.
Hence, the correct answer is option: 'C'.