We’re given the following first order reaction:

A → B k = 0.83 min^{–1}

The ** integrated rate law** for a first order reaction is as follows:

$\overline{){\mathbf{ln}}{\mathbf{\left[}\mathbf{A}\mathbf{\right]}}_{{\mathbf{t}}}{\mathbf{}}{\mathbf{=}}{\mathbf{}}{\mathbf{-}}{\mathbf{kt}}{\mathbf{}}{\mathbf{+}}{\mathbf{}}{\mathbf{ln}}{\mathbf{\left[}\mathbf{A}\mathbf{\right]}}_{{\mathbf{0}}}}$

where **[A] _{t}** = concentration at time t,

We’re being asked to calculate** the amount of A** after **15 mins** if we start with** 3.6 M A**.

This means we have:

**[A] _{0} = 3.6 M k = 0.83 min^{–1}**

**[A] _{t} = ?**

The reaction A → B follows first order kinetics with k = 0.83 min^{–1}. If the initial concentration of A is 3.6 M, what is the concentration of A after 15 minutes?

A. 0.046 M

B. 0.230 M

C. 1.1×10^{–1} M

D. 1.84×10^{–3} M

E. 1.4×10^{–5} M

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 Integrated Rate Law concept. You can view video lessons to learn Integrated Rate Law. Or if you need more Integrated Rate Law practice, you can also practice Integrated Rate Law practice problems.