Solute is a substance that is dissolved into another substance (known as a solvent) to form solution. A common example of a solute is common salt (sodium chloride). When mixed in water (a solvent), we get salt water. Another commonly used solute (from our day to day life) is sugar, which is usually added in tea or milk or coffee. In general, the solute has lesser quantity in comparison to solvent (think of how much sugar do we add in a cup of tea, maybe a teaspoon full in 150-200 ml solvent). Solutes and solvent are, generally, different phases. For example, all the above mentioned examples have solid solutes in liquid solvent. However, we can also have liquid solute in liquid solvent (think about thinner solution in a bucket of paint).
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