How many atoms are in 181 g of calcume?

To calculate the number of atoms in 181 g of calcium, first determine the number of moles of calcium. The molar mass of calcium (Ca) is approximately 40.08 g/mol. Dividing 181 g by the molar mass gives about 4.51 moles of calcium. Since one mole contains Avogadro's number of atoms (approximately (6.022 \times 10^{23})), multiplying 4.51 moles by Avogadro's number results in approximately (2.72 \times 10^{24}) atoms of calcium.