- Joined
- Oct 27, 2008

I have a long list of chemicals in excel that I would like to include molecular weights for based on entered molecular formulas. I would like to know how I could enter the molecular formula as an argument and return the weight as a value.

Example:

Profenofos molecular formula (MF) is C11H15BrClO3PS and its molecular weight (MW) is ~373.65g/mol

This is calculated by multiplying the molar weight of each of the elements by their count and summing the total.

C = 12.01 * 11 = 132.11

H = 1.01 * 15 = 15.15

Br = 79.90 * 1 = 79.90

Cl = 35.45 * 1 = 35.45

O = 16.00 * 3 = 48.00

P = 30.97 * 1 = 30.97

S = 32.07 * 1 = 32.07

Then add up all the totals...

The math is easy, getting exact masses for the elements is also easy but making excel do it all as a function is something I havent been able to figure out.