Hopefully I can explain this to represent what I'm hoping I can do.

I have a basic concentration vs time chart. On the X axis I want to be able to change the spacing for each timpoint to be representative of the timepoint. What I mean is if you look at the chart now, the amount of space for the 7 hour timpoint is exactly the same as the 1/2 timepoint eventhough 7 hours is greater than 1/2 hour. Is there anyway to "normalize" the x axis to be representative of time?