You try to take the OD of undiluted Solution X The reading i

You try to take the OD of undiluted Solution X. The reading is off the scale (you cannot use your standard curve). How could you figure out the concentration of undiluted Solution X using just the information you have?

Solution

The concentration of solution X can be calculated by using the formula below provided a standard graph has been worked out by the running the standard under varying dilutions.

Though the value of OD of Solution X runs out off the scale.

The Value of Standard chosen from the graph and it corresponding concentration can be used to calculate the concentration of the sample (solution X)

Concentration of the sample (solution X) = OD of the sample (solution X) / OD of the standard x conc. of the standard.