Question 474871
You have 100 mL of 10% acid,how many mL of 100% acid do you need to add to make the solution 20%?
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let x=ml of 100% acid to add
10%(100)+100%x=20%(100+x)
10+x=20+.2x
.8x=10
x=10/.8=12.5
ans:
amt of 100% acid to add=12.5 ml