Question
Question: In countries near to the polar region, the roads are sprinkled with \(CaC{l_2}\). This is: A. To m...
In countries near to the polar region, the roads are sprinkled with CaCl2. This is:
A. To minimize the snowfall
B. To minimize pollution
C. To minimize the accumulation of dust on roads
D. To minimize the wear and tear on roads.
Solution
Calcium chloride is an inorganic salt and is a white colored crystalline solid at room temperature. It is highly soluble in water and also is hygroscopic that means it can attract ana absorbed water molecules from surroundings.
Complete step by step answer:
In countries near to the polar region, the roads are sprinkled with calcium chloride to minimize the snowfall as it causes depression in the freezing point as a result the snow melts into a liquid state. Thus calcium chloride acts as a de-icing agent. To minimize the snowfall some amount of sodium chloride is also sprinkled with calcium chloride.
So, the correct answer is Option A.
Additional information:
The decrease in the freezing point of the solution by the addition of non-volatile solute as compared to the freezing point of pure solvent is known as depression in freezing point. Mathematically it is given as:
ΔTf=Tf∘−Tf
Where Tf= freezing point of the solution
Tfo= freezing point of the pure solvent.
The depression is directly proportional to the molality. That means it depends upon the number of solute particles. Thus we can say depression in freezing point is a colligative property.
Note: Calcium chloride is also used as an additive in plastics, wastewater treatment plants, and blast furnaces to improve the process. It also acts as a pH buffer for hardening the swimming pool water to reduce erosion of pool concrete. It is also used for dust suspension. Due to hygroscopic nature, it acts as an excellent desiccant for removing dissolved water in liquids