Question

What is the molecular weight of sulfuric acid?

Answer 1

Hint: The molecular weight or the molar mass of any compound is the sum of the masses of all the atoms present in that compound. The molecular weight is measured in grams per mole. It is the weight of any atom in 1 mole that is $6.022\times {{10}^{23}}$ particles of that atom. So it is measured in g/mol.

Complete answer:
Molecular weight of any molecule is the sum of mass of the individual atoms present in that molecule. We have been given to find the molecular weight of sulfuric acid. Sulfuric acid has the formula of${{H}_{2}}S{{O}_{4}}$. As from the formula we can see that sulfuric acid contains 2 hydrogen atoms, one sulfur atom, and 4 oxygen atoms. The molecular weight will be the sum of all the masses of these atoms. The quantity of 2 hydrogen atoms will be multiplied with molar mass of hydrogen and that of 4 oxygen atoms will be multiplied by molar mass of oxygen.
The molecular mass of hydrogen (H) is 1 g/mol, sulfur (S) is 32 g/mol and that of oxygen (O) is 16 g/mol. Therefore the molecular weight of${{H}_{2}}S{{O}_{4}}$will be,
Molecular weight = 2(H) + S + 4(O)
Molecular weight = 2(1) + 32 + 4(16)
Molecular weight = 2 + 32 + 64
Molecular weight = 98 g/mol
Hence, the molecular weight of ${{H}_{2}}S{{O}_{4}}$ is 98 g/mol or 98 u.

Note:
The molar mass or the mass number of any atom is the sum of the protons and the neutrons present in that atom. The number of protons is equal to the atomic number of that atom. The molar mass of any substance in gram is measured in gram per mole, also as ‘u’ that stands for unified mass and denotes gram per mole.