what is the percent concentration of the resulting mixture? Round to the nearest tenth of a percent.

Question

A student mixed 50ml of a 3% hydrogen peroxide solution with 30 ml of a 12% hydrogen peroxide solution. Find the percent concentration of the resulting mixture. Round to the nearest tenth of a percent.

Answer 1

First we find out how many total milliliters we have of the final solution:

 

50ml + 30ml = 80 total ml

 

Then we find out how many of those milliliters are hydrogen peroxide:

 

.03(50ml) + .12(30ml) = 5.1 ml of hydrogen peroxide

 

Then we just divide to find the new concentration:

 

5.1 / 80 = 0.06375 = 6.4% (rounded)