In March of 2007 a number of pets were sickened or killed by pet food contaminated with the chemical melamine which is used in the manufacture of certain plastics. It is thought that the melamine was added to make a pet food additive appear to have more protein than it really did. Protein content is determined by measuring nitrogen content of food since protein is the main source of nitrogen in food. What is the % by mass of nitrogen in melamine which has the formula C₃H₆N₆?

Question

Quizplus · Accepted Answer

To find the % by mass of nitrogen in melamine (C₃H₆N₆), calculate the molar mass of melamine and the total mass of nitrogen in it. The molar mass of melamine is (3*12.01) + (6*1.01) + (6*14.01) = 126.12 g/mol. The mass of nitrogen is 6*14.01 = 84.06 g/mol. The % by mass of nitrogen is (84.06/126.12) * 100% = 66.6%.

In March of 2007 a Number of Pets Were Sickened