Question

4-A major textile dye manufacturer developed a new yellow dye. The dye has a percent composition of 75.95% X, 17.72% N, and 6.33% H by mass with a molar mass of about 240 g/mol. Determine the molecular formula of the dye.

Answer 1

Answer:

C₁₅N₃H₅

Explanation:

Let's assume we have 240 g of the dye (1 mol), in that case we'd have:

• 240 g * 75.95/100 =  182.28 g of C

• 240 g * 17.72/100 =  42.53 g of N

• 240 g * 6.33/100 =  15.19 g of H

Now we convert the masses of each element into moles, using their respective molar masses:

• 182.28 g C ÷ 12 g/mol = 15.19 mol C ≅ 15

• 42.53 g N ÷ 14 g/mol = 3.04 mol N ≅ 3

• 15.19 g C ÷ 1 g/mol = 15.19 mol H ≅ 15

Thus the molecular formula is C₁₅N₃H₅.