Question

Which of the following is a true solution?
A) Copper in gold
B) Sulphur in water
C) Milk
D) Water in Sulphur dioxide

Answer 1

Hint:We know that a true solution is the homogeneous mixture of two or more than two substances dissolved in the solvent in which the substance or solute has the particle size of less than or so because of the extremely small size of the particles they cannot be separated through the filter paper and also are not visible to the naked eye.


Complete solution:
To make it easy first we will filter the option on the basis of homogeneity, so copper in gold is the only one solution which is homogeneous in nature as we know that copper and gold are mixed together to form an alloy. They form a solid – solid homogeneous mixture therefore copper in gold will be an example of a true solution.
On the other hand, milk is an example of a suspension solution. A suspension is defined as a heterogenous mixture in which the solid particles are distributed throughout the liquid without dissolving it.
So, Sulphur in water will also be a heterogeneous suspension solution as they can be separated easily by the method of filtration.
Sulphur dioxide is fairly soluble in water and it reacts with water to form sulphuric acid so it is not a solution as it readily reacts with water.

So, the correct answer will be Option A.


Note: In order to differentiate between true solutions and colloidal solutions we use the process of tyndall effect which happens as when light passes through the solution then, if it is a colloidal solution, it will scatter the light on the other hand true solutions will show no light. This happens because the particles in true solutions are not large enough to disperse the light.