Answer:
126g/mol
Explanation:
Molar mass is the mass of all the atoms in a molecule or compound in grams per mole (g/mol or gmol-1). To calculate the molar mass of a molecule, we first obtain the atomic weights of the individual elements in a periodic table. We then count the number of atoms and multiply it by the individual atomic masses.
•Atomic weight of Sodium Na = 23g/mol
•Atomic weight of Sulphur S= 32g/mol
•Atomic weight of Oxygen O = 16g/mol
•Find the sum of the atomic weights / molar masses of all the elements.
We have 2 atoms of Sodium Na and three atoms of Oxygen O. This implies that we will have to multiply the number of their atoms present by their atomic masses/molar masses.
Molar mass of Na2SO3= (number of atoms × atomic mass of Na) + (number of atoms × atomic mass of S) + ( number of atoms × atomic mass of O)
Molar mass of Na2SO3= (2×23g/mol) + (1×32g/mol) + (3×16g/mol)
Molar mass of Na2SO3= 46g/mol + 32g/mol + 48g/mol
Molar mass of Na2SO3 = 126g/mol
Therefore the molar mass of Na2SO3 is 126g/mol
