To 50 mL of 0.5 M H2SO4, 75 mL of 0.25 M H2SO4 is added. What is the concentration of the final solution if its volume is 125 mL?
How many millilitres of 0.1 M H2SO4 must be added to 50 mL of 0.1 M NaOH to give a solution that has a concentration of 0.05 M in H2SO4?