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Assertion: K2Cr2O7 is used as primary st...

Assertion: `K_2Cr_2O_7` is used as primary standard in volumetric analysis.
Reason: It has a good solubility in water.

A

if both Assertion and Reason are true and reason is the correct explanation of the assertion.

B

if both assertion and reason are true but reason is not the correct expalanation of the assertion

C

if assertion is true, reason is false

D

both assertion and reason are false statements.

Text Solution

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The correct Answer is:
To solve the question, we need to evaluate the assertion and reason provided: **Assertion:** \( K_2Cr_2O_7 \) is used as a primary standard in volumetric analysis. **Reason:** It has a good solubility in water. ### Step-by-Step Solution: 1. **Evaluate the Assertion:** - Potassium dichromate (\( K_2Cr_2O_7 \)) is indeed used as a primary standard in volumetric analysis. - A primary standard must be stable, pure, and not hygroscopic. \( K_2Cr_2O_7 \) meets these criteria as it is stable in the atmosphere, can be obtained in pure form, and does not absorb moisture from the air. 2. **Evaluate the Reason:** - The reason states that \( K_2Cr_2O_7 \) has good solubility in water. - However, while \( K_2Cr_2O_7 \) is soluble in water, it is important to note that it is not soluble in cold water. This means that the statement about its solubility being "good" is misleading, as it is not soluble at lower temperatures. 3. **Conclusion:** - The assertion is true because \( K_2Cr_2O_7 \) is a primary standard. - The reason is false because it does not have good solubility in cold water. - Therefore, the correct relationship is that the assertion is true, and the reason is false. ### Final Answer: The correct option is: **Assertion is true, and Reason is false.** ---
To solve the question, we need to evaluate the assertion and reason provided: **Assertion:** \( K_2Cr_2O_7 \) is used as a primary standard in volumetric analysis. **Reason:** It has a good solubility in water. ### Step-by-Step Solution: 1. **Evaluate the Assertion:** ...
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