Question

How would you make a 2-L solution of 0.01639 N H₂SO₄ using 36N (concentrated) H₂SO₄?, what volume of H₂SO₄ (in microliters) would you measure and dilute to a 2-L volume?

Answer 1

Normality of an acid=Gram equivalent weight of the acid per litre of the acidic solution

Gram equivalent weight of an acid=Gram molecular weight of the acid/Number of hydrogen ions per molecule it provides in solution

For , each molecule provides 2 hydrogen ions (H⁺)

So normality of ={Gram molecular weight of /2}÷Volume of solution (in L)

Gram molecular weight of =2xGram atomic weight of H+1xGram atomic weight of S+4xGram atomic weight of O

=2x1 g+32 g+4x16 g=98 g

So gram equivalent weight of =98 g/2=48 g eq

For given 36 N (N₁), we need to find volume (V₁ )required to make 2.0 L (V₂) of 0.01639 N (N₂)

So

36 Nx V₁=0.01639 Nx2.0 L

So V₁=0.01639 Nx2.0 L/36 N

=0.00091055 L

=910.55 microliters (1 L=1000000 microliters)

So the answer is 910.55 microliters of 36 N sulphuric acid is required to make 2.0 L of 0.01639 N sulphuric acid.