For my homework I got this problem that my professor never went over in class how to do it and I don't know how to interpret it.
A chemist runs a second order reaction of A->B starting at 10mili moles/L concentration of A (and no B). After one hour the concentration of the product has reached 6mili moles/L. Plot the concentration of B over the time until it reaches 9mili moles.
Do I start with this formula:
1/[A7]=kt+(1/A0)
How would I solve this problem and how would I put it in excel?
If you could help me out, I would really appreciate it.
To solve this problem, you can use the integrated rate law for a second-order reaction:
1/[A]t = kt + 1/[A]0
Where:
[A]t = concentration of A after time t
[A]0 = initial concentration of A
k = rate constant of the reaction
t = time
In this case, [A]t represents the concentration of A, and by extension, B, since the reaction is converting A to B.
Given that the concentration of A at t=0 is 10 milli moles per liter (mmol/L), and the concentration of B at t=0 is 0 mmol/L, and that after one hour, the concentration of B has reached 6 mmol/L, we can now solve for the rate constant.
Considering the initial concentration of A ([A]0 = 10 mmol/L) and the concentration of A after one hour ([A]t = 6 mmol/L), we can rearrange the integrated rate law equation:
1/[A]t - 1/[A]0 = kt
Substituting the known values:
1/6 - 1/10 = k * 1
Simplifying:
2/15 = k
Therefore, the rate constant k is 2/15.
To plot the concentration of B over time until it reaches 9 mmol/L, you can use an Excel spreadsheet. Follow these steps:
1. Create two columns: one for time (t) and another for the concentration of B ([B]).
2. In the time column, enter the time intervals at which you want to measure the concentration.
3. In the [B] column, apply the following formula for each time interval: [B] = kt + 1/[A]0
4. Input the initial concentration of A (10 mmol/L) into the formula.
5. Copy the formula down the [B] column until the concentration of B reaches 9 mmol/L.
6. Plot the [B] column against the time column using a scatter plot or line graph.
This will give you a plot of the concentration of B over time until it reaches 9 mmol/L.