Answer:
0.375 M
Explanation:
NaOH(aq) + HBr(aq) ------------> NaBr(aq) + H2O(l)
Concetration of acid CA= 0.250M
Concentration of base CB= ????
Volume of acid VA= 30.0mL
Volume of base VB= 20.0mL
Number of moles of acid nA= 1
Number of moles of base nB= 1
CA VA/CB VB= nA/nB
CB= CAVAnB/VB nA
= 0.25× 30×1/20×1= 0.375 M