An increase in temperature increases the rate of dissolution of a solute in a solvent. We can notice this at home by doing simple experimentation. Try dissolving some sugar in a glass of cold water, for example 1 teaspoonful. Then try to dissolve the same amount of sugar in a glass of hot water. One can easily see that it is much easier and much faster to dissolve sugar in hot water. 

When heat is added to a substance, the molecules of the substance gain kinetic energy and start moving much faster. Due to the speed of these molecules, the chances of interaction between solute and solvent molecules increases. This causes an increase in the rate of dissolution and we see that solute dissolves much faster in solvents with higher temperature.

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What is the effect of temperature on the rate of dissolving?  

An increase in the temperature increases the rate of dissolving a solute in a given solution. When a solute is added to a solution, the molecules of solute and solution bump into each other and this causes the dissolving of solute. At low temperatures, the solvent molecules have low energy and hence less chances of collision are there. When we raise the temperature of the solvent, its molecules have more kinetic energy and move at a much faster rate. This causes more collision between solvent and solute molecules and hence faster dissolution of solute. 

An example is the mixing of sugar in water, when making tea. We can observe that a sugar cube takes a while to dissolve in a cup of water that came straight out of tap. In comparison, if we were to boil the water, the sugar cube will dissolve much faster. 

Hence, temperature increases the rate of dissolving of a solute.

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