There are 0.50 moles of the solute particles in the solution. The solute in a solution is the substance that is present in lesser amount. So, it is glucose the solute in this system. Glucose is held by covalent compounds so when dissolved in water it does not dissociates and would still be the glucose molecule. Therefore, the number of moles added to the solvent is equal to the number of moles of solute particles in the solution.