Question

Lead (II) chromate, PbCrO4, was used as a pigment in paints. How many atoms are in 25 g?

Answer 1

4.658 * 10^22 atoms

Step-by-step explanation:

Mass = 25 g

Number of atoms = ?

Number of moles = Mass / Molar mass

Molar mass of PbCrO4 = 323.1937 g/mol

Number of moles = 25 g / 323.1937 g/mol

Number of moles = 0.077352993 moles

1 mol = 6.022 * 10^23 atoms

0.077352993 mol = x

Solving for x;

x = 0.077352993 * 6.022 * 10^23 / 1

x = 4.658 * 10^22 atoms