Answer to Question #171795 in General Chemistry for Leoni

Question

Calculate the number of iodine atoms in 3.50g of iodine molecules. Give your answer to 3 significant figures. The Avogadro constant is 6.022*1022 mol-1.

Answer 1

mass of I₂ = 3.50 g

molar mass of I₂ = 253.81 g/mol

number of moles of I₂ = $\dfrac{3.50g}{253.81g/mol} = 0.0138\ moles$

1 mole of Iodine molecule = 2 moles of Iodine atoms

0.0138 moles of Iodine molecules = 0.0276 moles of Iodine atoms

1 mole of Iodine atom = 6.022 × 10²³ atoms

$\therefore$ 0.0276 moles of Iodine atom = 1.662 × 10²² atoms