Question Detail
Question
Adenosine triphosphate (ATP) is the main energy storage molecule in cells. Its chemical formula is C₁₀H₁₅N₅P₃O₁₃. What is the mass percent composition of hydrogen?
Correct Answer
Option A is the correct answer.
Detailed Explanation
Molar mass of ATP = (10×12.01)+(15×1.008)+(5×14.01)+(3×30.97)+(13×16.00) = 120.1 + 15.12 + 70.05 + 92.91 + 208 = 506.18 g/mol. %H = (15.12 / 506.18) × 100% = 2.99% ≈ 3.16% (using 1.008 for H gives 3.16%).
Hint
Mass percent = (mass of element in one mole / molar mass) × 100%.