Answer:
75 mL
Step-by-step explanation:
Let's consider the neutralization reaction between NaOH and HCl.
NaOH + HCl → NaCl + H₂O
The moles of HCl that reacted are:
0.030 L × 0.50 mol/L = 0.015 mol
The molar ratio of NaOH to HCl is 1:1. The moles of NaOH that reacted are 0.015 moles.
The volume of 0.20 M NaOH that contains 0.015 moles is:
0.015 mol / (0.20 mol/L) = 0.075 L = 75 mL