What is the percentage by mass of hydrogen in nitroglycerin?

Sure, to find the percentage by mass of hydrogen in nitroglycerin, we need to follow these steps:

1. First, we need to know the molecular formula of nitroglycerin, which is C3H5N3O9.

2. Next, we need to calculate the molar mass of nitroglycerin. To do this, we add up the molar masses of all the atoms in the formula. The molar mass of carbon (C) is approximately 12.01 g/mol, hydrogen (H) is approximately 1.01 g/mol, nitrogen (N) is approximately 14.01 g/mol, and oxygen (O) is approximately 16.00 g/mol.

   So, the molar mass of nitroglycerin is (312.01 g/mol) + (51.01 g/mol) + (314.01 g/mol) + (916.00 g/mol) = 227.09 g/mol.

3. Then, we need to find the total mass of hydrogen in the formula, which is 5*1.01 g/mol = 5.05 g/mol.

4. Finally, we calculate the percentage by mass of hydrogen in nitroglycerin by dividing the total mass of hydrogen by the molar mass of nitroglycerin and then multiplying by 100 to get the percentage.

   So, the percentage by mass of hydrogen in nitroglycerin is (5.05 g/mol / 227.09 g/mol) * 100 = 2.22%.

Therefore, the percentage by mass of hydrogen in nitroglycerin is approximately 2.22%.