# Calculate the molar concentration of substrate

## Homework Statement

Hello,
I'm creating a Michealis/Menten curve and need to find the X values for the graph.

## Homework Equations

These are the instructions given to find the X values:

To obtain the X value, plot the molar concentration (molarity) of substrate used in each well.

You can determine this by multiplying the volume of substrate added to each well by the concentration of the substrate (1 mg/ml or 1 ug/ul) to give you a mass.

Paranitrophenylphosphate (the substrate) has a formula weight of 275 g/mole.

The substrate is diluted in 100uL in each well.

Using these values, calculate the molar concentration of substrate in each well across the plate. These are the X values. You are now ready to plot the kinetics curve.

## The Attempt at a Solution

Using one data set of for 10uL of substrate i calculated moles
First converted the 10uL to .010mL

.010mL * 1 mg/ml = .010mg mass of substrate

Converted the .010mg to grams and solved for moles

1.000 x10-5g (1mol / 279g) = 3.58 x10e-8 moles

converted the 100ul to liters

100e-6uL = 1.000e-4 L

then found found moles\liters

3.58 x10e-8 moles / 1.000e-4 L = 3.580e-4 M

Not sure if this is correct or not. I also tried taking the 10ug / 100ul = .100 ug/uL and doing something with that, but got totally lost....