Question 424443
90% sulfuric acid=10% water
.90m+5(1.00)=.5(m+5)
.90m+5=.5m+2.5
.4m=2.5
m=2.5/.4=6.25
You started with 6.25 liters of 90% solution.  Add the 5 liters of distilled water, and you have 11.25 liters of a 50% solution..