Question

Tetracycline is an antibiotic used to treat infections that cause cholera, malaria, and syphilis, among others. The formula is C22H24N2O8 (MM = 444.435 g/mol). Calculate how many ug of nitrogen is present in 30.45 g of tetracycline?

Answer 1

Solution

mass of tetracycline = 30.45 g

molar mass of tetracycline = 444.435 g/mol

No. of mole of tetracycline = mass / molar mass = (30.45 g)/(444.435 g/mol) = 0.06851 mol

The molecular formula of tetracycline is C₂₂H₂₄N₂O₈

From the molecular formula of tetracycline, it is clear that 1 mol of tetracycline contains 2 mol of Nitrogen.

Thus, no. of mol of Nitrogen in tetracycline = 2 x 0.06851 mol = 0.1370 mol

The molar mass of Nitrogen = 14.00 g/mol

Total mass of nitrogen = No. of mol of nitrogen x molar mass of nitrogen

= (0.1370 mol) x (14.00 g/mol)

= 1.9184 g

convert g to ug (microgram)

since 1 g = 10⁶ ug

therefore,  1.9184 g = 1.9184 x 10⁶ ug

Total mass of nitrogen in ug = 1.9184 x 10⁶ ug (Ans)