When a certain amount of solid A is dissolved in \( 100 \, \mathrm{g} \) of water at \( 25^\circ \mathrm{C} \) to make a dilute solution, the vapour pressure of the solution is reduced to one-half of that of pure water. The vapour pressure of pure water is \( 23.76 \, \mathrm{mm \, Hg} \). The number of moles of solute A added is ________. (Nearest Integer)
