At what temperature (in °C) will the NaCl stop melting ice when there is 7.5 mol of NaCl in 6.95 kg of H₂O?

3 answers

I don't understand the question. Is there more to the problem? Is this a subpart of a larger question?
...no. That was all we were given.
OK. Perhaps this is what they want.
dT = i*Kf*m
m is given as m = mols NaCl/kg solvent
Kf is 1.86 C/m for water
i is 2
Substitute and you get delta T. Subtract that from zero C to get the temperature at which water will freeze under those conditions.