How many atoms of H are present in 31.30 grams of formaldehyde (CH2O)?

• A. 7.52 × 10^{24} atoms
• B. 1.88 × 10^{24} atoms
• C. 6.02 × 10^{23} atoms
• D. 3.76 × 10^{24} atoms

Answer: (D)

Verified step by step guidance

1. Calculate the molar mass of formaldehyde (CH\_2O) by summing the atomic masses of its constituent atoms: carbon (C), hydrogen (H), and oxygen (O). Use the atomic masses approximately as C = 12.01 g/mol, H = 1.008 g/mol, and O = 16.00 g/mol. The molar mass is given by \(M = 12.01 + 2 \times 1.008 + 16.00\) g/mol.
2. Determine the number of moles of formaldehyde in 31.30 grams by using the formula \(n = \frac{\text{mass}}{\text{molar mass}} = \frac{31.30}{M}\), where \(M\) is the molar mass calculated in the previous step.
3. Calculate the total number of formaldehyde molecules by multiplying the number of moles by Avogadro's number (\(N_A = 6.022 \times 10^{23}\) molecules/mol): \(N = n \times N_A\).
4. Since each molecule of formaldehyde contains 2 hydrogen atoms, multiply the total number of molecules by 2 to find the total number of hydrogen atoms: \(N_H = 2 \times N\).
5. Express the final answer in scientific notation to match the format of the given options.