Answer: 248mL
Step-by-step explanation:
Given:
Concentration of buffer solution Cs = 1.24%w/v of boric acid
Concentration of boric acid solution Cb = 5 % w/v boric acid
For 1 liter of buffer solution, the weight of boric acid needed is:
mb = 1 × 1.24 = 1.24 unit weight
mb = Cb × Vb .....1
Cb = concentration of boric acid solution.
Vb = volume of boric acid solution needed.
mb = weight of boric acid needed.
From equation 1.
Vb = mb/Cb
Vb = 1.24/5
Vb = 0.248L
Vb = 248mL