Question

# 1. Calculate the molality of benzoic acid / TBOH

solution and use the measured ΔTf (the change in freezing points) to calculate the value of Kf for TBOH.

Change in freezing points is 9.1 c

TBOH used is 3.2071g and Benzoic Acid used is 0.4083g

2. Obtain the freezing point of the unknown compound/ TBOH solution from the plateau of the curves. Use your calculated Kf value above for TBOH and the measured ΔTf of the unknown compound (the change in freezing points) to calculate the molality of the unknown compound/ TBOH solution. Finally calculate the molecular weight of the unknown compound (MW = grams / moles).

Change in freezing points is 12 c

TBOH used is 3.1579g and Unknown used is 0.5092g