A substance will be deliquescent if its vapour pressure
- is equal to the atmospheric pressure
- is equal to that of water vapour in air
- is less than that of water vapour in air
- is greater than that of water vapour in air
The Correct Option is C
Approach Solution - 1
Approach Solution -2
Deliquescence occurs when a substance absorbs moisture from the atmosphere until it dissolves in the absorbed water and forms a solution. This happens when the vapour pressure of the solution formed is lower than the partial pressure of water vapour in the surrounding air. Therefore, the substance becomes deliquescent when its vapour pressure is less than that of water vapour in the air.
So, the correct option is (C): less than that of water vapour in air.
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Concepts Used:
Solutions
A solution is a homogeneous mixture of two or more components in which the particle size is smaller than 1 nm.
For example, salt and sugar is a good illustration of a solution. A solution can be categorized into several components.
Types of Solutions:
The solutions can be classified into three types:
- Solid Solutions - In these solutions, the solvent is in a Solid-state.
- Liquid Solutions- In these solutions, the solvent is in a Liquid state.
- Gaseous Solutions - In these solutions, the solvent is in a Gaseous state.
On the basis of the amount of solute dissolved in a solvent, solutions are divided into the following types:
- Unsaturated Solution- A solution in which more solute can be dissolved without raising the temperature of the solution is known as an unsaturated solution.
- Saturated Solution- A solution in which no solute can be dissolved after reaching a certain amount of temperature is known as an unsaturated saturated solution.
- Supersaturated Solution- A solution that contains more solute than the maximum amount at a certain temperature is known as a supersaturated solution.