The volume of 0.025 M H3PO4 required for the complete neutralisation of 25 ml of 0.03 M Ca(OH)2 solution is:
30.0 mL of the given HCl solution requires 20.0 mL of 0.1 M sodium carbonate solution for complete neutralisation. What is the volume of this HCl solution required to neutralise 30.0 mL of 0.2 M NaOH solution?