200 g of a 10 percent solution is mixed with 300 g of a 20 percent solution. What is the final mass percent?
Answer and explanation
Correct answer: 16 percent
The first solution contains 10% of 200 g, or 20 g, solute. The second contains 20% of 300 g, or 60 g, solute. Thus total solute is 80 g and total solution mass is 500 g. Final mass percent = (80/500) × 100 = 16%. The answer is not obtained by simply averaging the two percentages because the solution masses are different.
Frequently asked questions
What is the correct answer to this question?
16 percent
Why is this the correct answer?
The first solution contains 10% of 200 g, or 20 g, solute. The second contains 20% of 300 g, or 60 g, solute. Thus total solute is 80 g and total solution mass is 500 g. Final mass percent = (80/500) × 100 = 16%. The answer is not obtained by simply averaging the two percentages because the solution masses are different.
Which subject and chapter does this question cover?
This is a Class 11 Chemistry question. Chapter: Chapter 01: Solutions.
