Question

1). If I mix 6.28 mL of 1.000 M HCl, 10.94 mL of 0.005000 M I2, 15.27 mL of 4.000 M acetone, and 12.91 mL of water together, what is the new concentration of I2?

2). You have a reaction:

A + B --> C

The reaction is first order with respect to A and 2nd order with respect to B. If 0.2956 mol of A is mixed with 0.3868 mol of B to make a 1.000 L solution and the rate of the reaction is 0.4568 M/s, what is the rate constant (k)?

Answer 1

1)

new concentration of I2 = millimoles of I2 / total volume

                                    = 10.94 x 0.005 / (6.28 + 10.94 + 15.27 + 12.91)

                                  = 0.001205 M

2)

rate = k [A ] [ B]^2

0.4568 = k (0.2956) (0.3868)^2

k = 10.33 M^-2 s^-1

the rate constant (k)= 10.33 M^-2 s^-1