How many atoms are present in 12 grams (1 mole) of carbon-12?

• A. 1.00 × 10^{22} atoms
• B. 6.022 × 10^{23} atoms
• C. 12 × 10^{23} atoms
• D. 3.01 × 10^{23} atoms

Answer: (B)

Verified step by step guidance

1. Recognize that 12 grams of carbon-12 corresponds to exactly 1 mole of carbon atoms because the molar mass of carbon-12 is 12 g/mol.
2. Recall Avogadro's number, which is the number of atoms in one mole of any substance. Avogadro's number is \$6.022 \times 10^{23}$ atoms/mole.
3. Since you have 1 mole of carbon-12 atoms, the total number of atoms is equal to Avogadro's number multiplied by the number of moles.
4. Write the expression for the number of atoms: \(\text{Number of atoms} = 1 \text{ mole} \times 6.022 \times 10^{23} \text{ atoms/mole}\).
5. Conclude that the number of atoms in 12 grams of carbon-12 is \$6.022 \times 10^{23}$ atoms.