SOLUTION: A chemistry student needs to make a solution that is 70% water and 30% hydrochloric acid. The student's current mixture of 300 mL is 60% water and 40% hydrochloric acid. How much

Question 591392: A chemistry student needs to make a solution that is 70% water and 30% hydrochloric acid. The student's current mixture of 300 mL is 60% water and 40% hydrochloric acid. How much water must the student add to achieve his desired solution?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
A chemistry student needs to make a solution that is 70% water and 30% hydrochloric acid. The student's current mixture of 300 mL is 60% water and 40% hydrochloric acid. How much water must the student add to achieve his desired solution?
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Equation:
water + water = water
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0.60*300 + x = 0.70*(300+x)
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Multiply thru by 100 to get rid of the decimals.
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60*300 + 100x = 70*300 + 70x
30x = 10*300
x = 100 mL (amt of water to add)
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Cheers,
Stan H.
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