Question

The number of hydrogen atoms present in 25.6 g of sucrose (C\(_{12}\)H\(_{22}\)O\(_{11}\)) which has a molar mass of 342.3 g is

• A. \(22 \times 10^{23}\)
• B. \(9.91 \times 10^{23}\)
• C. \(11 \times 10^{23}\)
• D. \(44 \times 10^{23}\)

Hint:

Total atoms = (moles \(\times N_A\)) \(\times\) atoms per molecule.

Answer 1

The Correct Option is B

Step 1: Calculate number of moles of sucrose.
\[ n = \frac{\text{mass}}{\text{molar mass}} = \frac{25.6}{342.3} \approx 0.0748 \text{ mol} \]
Step 2: Find number of molecules.
\[ N = nN_A = 0.0748 \times 6.022 \times 10^{23} \approx 4.50 \times 10^{22} \]
Step 3: Find hydrogen atoms per molecule.
Each sucrose molecule has 22 H atoms.
Step 4: Total hydrogen atoms.
\[ N_H = 22 \times 4.50 \times 10^{22} = 9.90 \times 10^{23} \approx 9.91 \times 10^{23} \]
Final Answer:
\[ \boxed{9.91 \times 10^{23}} \]