chemistry
posted by danielle .
What is the halflife of a compound if 69 percent of a given sample of the compound decomposes in 59 min? Assume firstorder kinetics.

The boiling point of diethyl ether CH3CH2OCH2CH3 is 34.500C at 1 atmosphere. A nonvolatile, nonelectrolyte that dissolves in diethyl ether is cholesterol .
How many grams of cholesterol, C27H46O (386.6 g/mol), must be dissolved in 263.0 grams of diethyl ether to raise the boiling point by 0.4500C ? 
ln(No/N) = kt
Assume No = 100, then N = 31 after 69% has decomposed. Plug in 59 min for t and calculate k.
Then go to k=(0.693/t_{1/2}) and calculate t_{1/2}. The halflife will be in minutes.