Question

Levamisole is a medication used to treat parasitic worm infections. It contains carbon, hydrogen, nitrogen, and sulfur in the following percentages: Carbon 64.67%, Hydrogen: 5.92%, and Nitrogen 13.71%.a) Determine the empirical formulaB) what do you need to determine the molecular formula?

Answer 1

1st step - Determine the minimum formula using the percentage formula. We consider that the percentage of each compound is for 100g of the compound. Then, we divide the mass quantity by the atomic mass of the element:

Carbon:

64.67/12 = 5.389

Hydrogen:

5.92/1 = 5.92

Nitrogen:

13.71/14 = 0.9793

Now we divide each number by the smallest number (0.9793):

C - 5.389/0.9793 = 5.5

H - 5.92/0.9793 = 6

N - 0.9793/0.9793 = 1

The value of C is decimal. So we need to transform it into an integrer. Let's multiple by 2:

C - 11

H - 12

N - 2

a) The empirical formula is C11H12N2