Question

High humidity in storage can be reduced by keeping

• A. CaCl\(_2\)
• B. KMnO\(_4\)
• C. KNO\(_3\)
• D. Urea

Hint:

In post-harvest and storage questions, remember the specific roles of common chemicals: Calcium chloride (CaCl\(_2\)) and silica gel are for absorbing moisture (desiccants), while Potassium permanganate (KMnO\(_4\)) is for absorbing ethylene (ethylene scavenger).

Answer 1

The Correct Option is A

Step 1: The Core Idea:
The objective is to identify a chemical compound that lowers excessive humidity in a storage area. High humidity indicates a high level of water vapor. Therefore, a substance that absorbs water is required. Such substances are called desiccants or hygroscopic agents.

Step 2: Analysis of Options:
Let's examine the options:
\[\begin{array}{rl} \bullet & \text{CaCl\(_2\) (Calcium chloride): This salt is highly hygroscopic, readily attracting and absorbing water. It is a very effective and common desiccant for drying enclosed spaces.} \\ \bullet & \text{KMnO\(_4\) (Potassium permanganate): A strong oxidizing agent. In storage, it primarily removes ethylene gas, a ripening hormone, slowing ripening. It does not absorb moisture.} \\ \bullet & \text{KNO\(_3\) (Potassium nitrate): This salt is mainly a fertilizer. While it can absorb some moisture, it's not an effective desiccant compared to calcium chloride.} \\ \bullet & \text{Urea: A nitrogenous compound used as fertilizer. It is also hygroscopic but not typically used as a desiccant for storage.} \\ \end{array}\]Based on these properties, calcium chloride is the best choice for reducing storage humidity.

Step 3: Conclusion:
To reduce high humidity in storage, use Calcium chloride (CaCl\(_2\)).