Problem: Cocaine is a weak organic base whose molecular formula is C17H21NO4. An aqueous solution of cocaine was found to have a pH of 8.53 and an osmotic pressure of 52.7 torr at 15 oC.Calculate Kb for cocaine.

FREE Expert Solution

We are being asked to calculate the Kb for a cocaine solution of which has a pH of 8.53 and an osmotic pressure of 52.7 torr at 15°C

Cocaine is a weak organic base whose molecular formula is C17H21NO4


Since we’re dealing with a weak base and Kb is an equilibrium expression, we will have to create an ICE chart to determine the equilibrium concentration of each species:

C17H21NOweak baseproton acceptor
H2O → will act as the weak acidproton donor


Equilibrium reaction:        C17H21NO4(aq) + H2O(l)  C17H21NO4H+(aq) + OH-(aq)

80% (66 ratings)
View Complete Written Solution
Problem Details

Cocaine is a weak organic base whose molecular formula is C17H21NO4. An aqueous solution of cocaine was found to have a pH of 8.53 and an osmotic pressure of 52.7 torr at 15 oC.

Calculate Kb for cocaine.

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Weak Bases concept. If you need more Weak Bases practice, you can also practice Weak Bases practice problems.

What professor is this problem relevant for?

Based on our data, we think this problem is relevant for Professor McCurdy's class at IOWA.