Question

What additional factors affect the rate of dissolution of ionic solids like salts?
(A) Enthalpy and entropy
(B) Enthalpy and surface area
(C) Entropy and temperature
(D) Enthalpy and temperature

Answer 1

The rate of dissolution is the transfer of rate of an individual molecule that is from the solid particles into the solution as individual free molecules or we can say the process in which a substance forms a solution. A rate of dissolution depends on the surface area of solute in a solid state, temperature of the solvent and the amount of stirring.

Complete answer:
We need to find the additional factors the rate of dissolution of ionic solids like salts depends on.
From the above given option the only option that affects the rate of dissolution is option (D) that is enthalpy and temperature.
Hence we can say enthalpy and temperature affect the rate of dissolution of ionic solids like salt. Positive change in enthalpy values indicates that the rate of dissolution of ionic salt is endothermic. While increase in temperature will increase the dissolution rate of the ionic solid like salt.
At the same time negative change in enthalpy indicates the rate of dissolution of ionic solid is exothermic and decrees in temperature will decrease the dissolution rate of the ionic solid like salt.
This is how the enthalpy and temperature affect the rate of dissolution.
Option (D) is correct answer.

Note:
Remember that there are other factors that can affect the rate of dissolution. If we want to increase the rate of dissolution we can also increase the size of the particle of the solid. Note that rate of dissolution plays a main role in dissolution of the drugs which is important for therapeutic effectiveness.