Question

A piece of aluminum foil has a mass of 27 grams. About how many atoms does this foil contain?

• A. $1.20\times {10}^{24}$ atoms
• B. $6.02\times {10}^{23}$ atoms
• C. $3.01\times {10}^{23}$ atoms
• D. 27 atoms
• E. 13 atoms

Answer 1

The correct option is B $6.02\times {10}^{23}$ atoms

The atomic mass of Al is 27 g/mol.

Hence, 27 g of Al corresponds to 1 mole.

1 mole of any element contains Avogadro's number of atoms.

Hence, 27 g ( 1 mole ) of Al contains $6.02\times {10}^{23}$ atoms.

Hence the correct option is B.