The sp.gravity of hydrochloric acid solution is 1.17.
So its density
So volime of 100g acid solution is
This 100g acid solution contains 33.4g acid.
Now the balanced equation of the reaction
This equation reveals that 1mol HCl or 36.5g HCl neutralises 1 mol NaOH or 40g NaOH.
Given that 1cc NaOH solution contains 0.042g NaOH.
1L solution contains 42g NaOH
Hence 5L NaOH will be neutralised by
So volume of HCl solution required for neutralisation