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Question
Thyroxine, an important hormone that controls the rate of metabolism in the body, can be isolated from the thyroid gland. If 0.453 g of thyroxine is dissolved in 10.0 g of benzene, the freezing point of the solution could be measured as 5.144ºC. Pure benzene freezes at 5.444ºC and has a value for the molal freezing-point-depression constant of Kf of 5.12ºC/m. What is the approximate molar mass of thyroxine?A) 773 g/mol
B) 7.73 g/mol
C) 7.73 x105g/mol
D) 42.6 g/mol
E) 11.3 g/mol
Answer
This answer is hidden. It contains 1 characters.
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