Suppose that the c=o group in a peptide backbone can be regarded as isolated from the rest of the molecule. given that the force constant of the bond in a carbonyl group is 908 n/m, calculate the vibrational frequency of (a) 12c=16o and (b) 13c=16o. what is the percentage change in the natural frequency upon 12c13cisotope substitution

"standard molar enthalpy:

h2o ( liquid water ) : - 285.8 kj/mole

h2o ( water vapor ) : - 241.8 kj / mole.

δhrxn = - 241. 8 - ( - 285.8 )= -241.8 + 285.8 = 44.0

answer: 44.0 kj"

some sources quote the lethal dose, for an average 170lbs opiate-naive individual is between 75 and 375 mg

"record the time to complete a chemical reaction" would most likely be part of a lab procedure.