Problem 3. A second order reaction is 40% complete at the end of 50 minutes. What is the value of the rate constant (provide proper units!)? In how many minutes will the reaction be 80% complete? (10 points) Problem 3. A second order reaction is 40% complete at the end of 50 minutes. What is the value of the rate constant (provide proper units!)? In how many minutes will the reaction be 80% complete? (10 points)