How many molecules are present in 5.0 g of methyl alcohol (CH_3OH)? (Molar mass of CH_3OH = 32.0 g/mol)

• A. 5.0 × 10^{23} molecules
• B. 3.0 × 10^{22} molecules
• C. 1.5 × 10^{23} molecules
• D. 9.4 × 10^{22} molecules

Answer: (D)

Verified step by step guidance

1. Identify the given information: mass of methyl alcohol (CH\_3OH) is 5.0 g, and the molar mass of CH\_3OH is 32.0 g/mol.
2. Calculate the number of moles of CH\_3OH using the formula: \(\text{moles} = \frac{\text{mass}}{\text{molar mass}} = \frac{5.0\ \text{g}}{32.0\ \text{g/mol}}\).
3. Recall that one mole of any substance contains Avogadro's number of molecules, which is \$6.022 \times 10^{23}$ molecules/mol.
4. Calculate the number of molecules by multiplying the moles of CH\_3OH by Avogadro's number: \(\text{molecules} = \text{moles} \times 6.022 \times 10^{23}\).
5. Express the final answer in scientific notation to compare with the given options.