Question

Monosodium glutamate is used to enhance the flavor of foods, it has the following composition: 13.6% Na; 35.5% C; 4.8% H; 8.3% N and 37.8% O, by mass.

What is the empirical formula of monosodium glutamate?

R= NaC5H8NO4

Answer 1

Assume you have 1g of your sample.

Then 13.6% of this sample is Na, that is 0.136g.

Since you are to find the empirical formula, you need to find the number of moles of Na in 0.136g. You can do that by dividing by the atomic mass of Na: n(Na)=0.136g / 23.0 g/mol = 0.00591 mol

Next, you repeat this for all the other elements.

The last step is to pick the smallest number of moles that you get and divide the others by it. That way you should arrive at whole number coefficients for the empirical formula. The element with the smallest number of moles gets 1 as its coefficient).