# chemistry

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assuming complete dissociation of the solute, how many grams of \rm KNO_3 must be added to 275 \rm mL of water to produce a solution that freezes at -14.5 ^\circ {\rm C}? The freezing point for pure water is 0.0 ^\circ {\rm C} and K_f is equal to 1.86 ^\circ {\rm C}/m.

• chemistry -

delta T = i*Kf*m
Solve for m.

m = moles KNO3/kg solvent
Solve for moles KNO3.

moles KNO3 = grams KNO3/molar mass KNO3
Solve for grams.
i = 2

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