In which of the following compound (s) will heat be absorbed on adding water? l. KNO\(_3\) II. Concentrated H\(_2\)SO\(_4\) III. NH\(_4\)CI

Answer Details

Heat is absorbed when a substance dissolves in water and the process is called endothermic. In this case, KNO3 and NH4CI are ionic compounds that dissolve in water to form ions, and this process is endothermic. On the other hand, concentrated H2SO4 is a molecular compound and does not dissociate into ions when mixed with water, so no heat is absorbed. Therefore, the compounds that will absorb heat when mixed with water are option I and III only, which is answer choice C.