For a college chemistry experiment, students need to prepare a solution containing ethylene glycol. They are each given 20 fluid ounces of a solution containing 2% ethylene glycol, to which they will add another solution that contains 12% ethylene glycol. How much of the 12% solution should they add to obtain a 5% ethylene glycol solution? Write your answer as a whole number or as a decimal rounded to the nearest tenth.____ fluid ounces
Q. For a college chemistry experiment, students need to prepare a solution containing ethylene glycol. They are each given 20 fluid ounces of a solution containing 2% ethylene glycol, to which they will add another solution that contains 12% ethylene glycol. How much of the 12% solution should they add to obtain a 5% ethylene glycol solution? Write your answer as a whole number or as a decimal rounded to the nearest tenth.____ fluid ounces
Denote 12\% Solution: Let's denote the amount of the 12\% solution to be added as x fluid ounces.
Calculate Ethylene Glycol: The amount of ethylene glycol in the original 20 fluid ounces of 2% solution is 20×0.02.Calculation: 20×0.02=0.4 fluid ounces of ethylene glycol.
Calculate Ethylene Glycol: The amount of ethylene glycol in the x fluid ounces of 12% solution is x×0.12.Calculation: x×0.12=0.12x fluid ounces of ethylene glycol.
Total Volume After Mixing: After mixing the solutions, the total volume of the solution will be 20+x fluid ounces, and the total amount of ethylene glycol will be 0.4+0.12x fluid ounces.
Equation for 5% Solution: To have a final solution of 5% ethylene glycol, the equation (0.4+0.12x)/(20+x)=0.05 must be true.
Multiply Both Sides: Multiply both sides of the equation by (20+x) to get rid of the denominator.Calculation: (0.4+0.12x)=0.05×(20+x)
Distribute 0.05: Distribute 0.05 on the right side of the equation.Calculation: 0.4+0.12x=1+0.05x
Rearrange Equation: Rearrange the equation to isolate x on one side.Calculation: 0.12x−0.05x=1−0.4
Combine Like Terms: Combine like terms.Calculation: 0.07x=0.6
Solve for x: Solve for x by dividing both sides by 0.07.Calculation: x=0.070.6
Perform Division: Perform the division to find the value of x.Calculation: x=8.57142857
Round to Nearest Tenth: Round the result to the nearest tenth.Calculation: x≈8.6 fluid ounces
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