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AMan24
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Homework Statement
Lauryl alcohol is obtained from coconut oil and is used to make detergents. A solution of 5.00 gram of lauryl alcohol in 0.100Kg of benzene freezes at 4.1 degrees Celsius. What is the molar mass of the lauryl alcohol?
Kf for benzene = 5.12, Freezing point of benzene is 5.5
Homework Equations
Molality = mol of solute/kg solvent
Delta T = (Kf) x (m)
The Attempt at a Solution
(4.1 - 5.5) = (5.12) x (m)
m = -0.27344
-0.27344 = (5.00g/mm)/0.100Kg
5/(-0.27344) x (0.100) = mm
molar mass = -182.855
So when I am doing delta t, its supposed to be final minus initial right? So I am doing the new temperature, 4.1, degrees as the final, and the unchanged or natural temperature, 5.5, as the initial. The answer would be the same thing just positive, but I am probably doing something wrong to have this negative answer. Is delta T supposed to be absolute value? Maybe its supposed to be 5.5 - 4.1, but that doesn't make sense, why would 5.5 be the final temp?
edit: I just found out that Delta T can mean different things. So for this formula, delta T is Tf^0 - Tf. So i figured it out
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