what is the freezing point of 0.05 M glucose(C6H12O6), 0.05 M NaCl, and 0.05 M MgCl2?

Answer 1

Here is a good lesson in chemistry and you need to learn it and put it practice today. Find the caps key and know when to use it. You certainly need it to start sentences as in the What above. You do NOT need it when you intend to write molality. The small m stands for molality; the cap M stands for molarity. So I assume you mean 0.05 m glucose, 0.05 m NaCl, and 0.05 m MgCl2.
One other point, you're looking for the freezing point of what? water? benzene? napthalene? just what?

delta T = i*Kf*m
Substitute and solve for delta T, then subtract that from the normal freezing point of the solvent.
i = van't Hoff factor.
i = 1 for glucose
i = 2 for NaCl
i = 3 for MgCl2