Molar and molecular weight of As2Se3

• Relative molecular weight of As2Se3: 386.7232
• Molar mass of As2Se3: 386.7232 g/mol (0.38672 kg/mol)

Calculation of the relative molecular and molar mass of As2Se3

• Mr[As2Se3] = Ar[As] * 2 + Ar[Se] * 3 = 74.9216 * 2 + 78.96 * 3 = 386.7232
• Molar mass (kg/mol) = Mr[As2Se3] : 1000 = 386.7232 : 1000 = 0.38672 kg/mol

As2Se3: percent composition by element

• Arsenic (As) = 149.8432 : 386.7232 * 100 = 38.747 %
• Selenium (Se) = 236.88 : 386.7232 * 100 = 61.253 %

Molar mass calculator