What is the total number of molecules of hydrogen in 0.25 mole of hydrogen gas (H_2)?

• A. 1.505 × 10^{23}
• B. 3.011 × 10^{23}
• C. 2.5 × 10^{22}
• D. 6.022 × 10^{23}

Answer: (A)

Verified step by step guidance

1. Identify the given quantity: 0.25 mole of hydrogen gas (H\_2).
2. Recall that 1 mole of any substance contains Avogadro's number of molecules, which is \$6.022 \times 10^{23}$ molecules/mole.
3. Set up the calculation to find the total number of molecules by multiplying the number of moles by Avogadro's number: \(\text{Number of molecules} = 0.25 \times 6.022 \times 10^{23}\).
4. Perform the multiplication to find the total number of hydrogen molecules in 0.25 mole of H\_2.
5. Express the final answer in scientific notation to match the format of the given options.