A solution may be defined as following:
A homogeneous mixture of two or more substances is called a solution. Homogeneous means physically and chemically uniform throughout. For example,
i) When a small amount of sodium chloride is dissolved in water, a homogeneous mixture so obtained is called a solution of sodium chloride in water. The solution of sodium chloride in water is homogeneous because the properties of the solution are the same throughout the solution.
Some other common solutions are,
(a) Sugar solution
(b) Copper Solphate solution
(c) Vinegar (vinegar is a solution of acetic acid in water).
ii) A homogeneous mixture of two (or more) miscible liquids is also called a solution. For example, ethanol (ethyl alcohol) dissolves in water to give a solution of ethanol (ethyl alcohol) in water.
Aqueous solutions of low molecular mass solutes are true solutions. For example, solutions of sodium chloride, copper sulphate, glucose, etc. in water are true solutions.
In common use, the term solution actually means true solution.