Question

Commercially available sulphuric acid contains 93% acid by mass and has a density of 1.84 gm/ cm^ 3 . calculate the molarity of the solution .

Answer 1

100g(or mL) of solution has 93 g of H₂SO₄ (g=mL)

No. of moles of H₂SO₄= wt/Mol.wt
= $\frac{93}{96}$

density of solution = 1.84g/cm³(or mL) (1cm³= 1mL)
mass/volume(in mL) = 1.84 g/mL
100g/volume(in mL)= 1.84g/mL
volume(in mL)=$\frac{100}{1.84}$
volume (in l)= $\frac{100}{1.84\times 1000}$

Molarity = no.of moles of solute/volume of solution in L
= $\frac{93}{96}\times \frac{100}{1.84\times 1000}$
​ = 17.8M