The question ask to find the number of particles in 1L of a 1% solution of KCl.
OK, so my understanding is that I start up with 1L=1000mL and 1% KCl = 1g KCl/100mL
Therefore,
(1g KCl/100mL) x (1000mL) x (1mol KCl/75g KCl) = 0.1333 mol KCl. And since KCl dissociates (let's assume completely) into K+(aq) and Cl-(aq), so the amount of particle solutes is 0.267 mol. Is my calculation correct?