Question

How many grams of sulphuric acid is to be dissolved to prepare 200mL aquaeas solutions having concentrations of (H3O+) ions 1 M at 25 degree temperatures

Answer 1

dissociation reaction of sulphuric acid is .....

$H_2SO_4\Leftrightarrow 2H^++SO_4^{2-}$

[ you should remember that hydrogen ion, H+ and hydronium ions , H3O+ both are same.]

in above reaction, it is clear that,

concentration of sulphuric acid = 1/2 × concentration of hydrogen ions or hydronium ions

so, concentration of sulphuric acid = 1/2 × 1 = 0.5 M

volume of solution is given, V = 200mL

we know, mole of solute = concentration of solution × volume of solution

= 0.5 × 200mL/1000 = 0.1

now, weight of sulphuric acid = mole × molecular weight

=0.1 × 98 = 9.8g