How many molecules are present in 2.5 mol of NaCl?

• A. 6.02 × 10^{23} molecules
• B. 3.01 × 10^{24} molecules
• C. 2.5 × 10^{23} molecules
• D. 1.51 × 10^{24} molecules

Answer: (D)

Verified step by step guidance

1. Understand that the problem asks for the number of molecules in a given amount of substance (2.5 mol of NaCl).
2. Recall Avogadro's number, which is the number of particles (atoms, molecules, ions) in one mole of a substance: \(6.02 \times 10^{23}\) particles/mol.
3. Use the formula to find the number of molecules: \(\text{Number of molecules} = \text{moles} \times \text{Avogadro's number}\).
4. Substitute the given values into the formula: \(\text{Number of molecules} = 2.5 \text{ mol} \times 6.02 \times 10^{23} \text{ molecules/mol}\).
5. Multiply the numbers and express the answer in scientific notation to find the total number of molecules in 2.5 mol of NaCl.