Which of the following can be determined if the boiling-point elevation, the mass of solute and the molality of a given solution are known.

The identity of the solute
The polarity of the solute
The size of a molecule of the solute The molecular weight of the solute

My answer: the molecular weight of solute
Reason: m= (mass of solute/M.M. solute)/(kg solvent)
But- I don't know how I'd be able to get the mass of the solvent. Is it possible for me to assume the solvent to be 1 L and convert that to kg?

1 answer

I think molar mass is the right answer. No, you may not assume the solvent is 1 L and that the density is 1 kg; however, you can assume you have a kg of solvent, that will tell you the moles of solute. And if the delta T is known, the problem must tell you, also, the mass of the solvent. Or if this is a problem and you are trying to work it in parts and you have posted just pieces of the problem, I suggest you post the entire problem as a new post.