Question #bc6af

2 Answers
Mar 24, 2017

Answer:

#"10. mL H"_2"O"_2#

Explanation:

A solution's volume by volume percent concentration, #"v/v %"#, is a measure of the number of milliliters of solute present for every #"100 mL"# of solution.

In other words, the volume by volume percent concentration tells you how many milliliters of solute you would have if you were to pick a #"100-mL"# sample of a given solution.

In your case, you know that the solution has a #3.0%# volume by volume concentration, which means that every #"100 mL"# of this solution contain #"3.0 mL"# of hydrogen peroxide, the solute.

Now, solutions are homogeneous mixtures, which means that the same the same composition throughout. This allows you to use the percent concentration as a conversion factor to determine how many milliliters of hydrogen peroxide you'd get in #"348 mL"# of solution.

#348 color(red)(cancel(color(black)("mL solution"))) * overbrace(("3.0 mL H"_2"O"_2)/(100color(red)(cancel(color(black)("mL solution")))))^(color(blue)("= 3.0% v/v")) = "10.44 g H"_2"O"_2#

The answer must be rounded to two sig figs, the number of sig figs you have for the percent concentration.

Therefore, you will have

#color(darkgreen)(ul(color(black)("volume H"_ 2"O"_ 2 = "10. mL")))#

Mar 24, 2017

Answer:

10.44mL #H_2O_2#

Explanation:

The antiseptic #H_2O_2# solution is 3.0% (v/v). This means that for every 100mL of the antiseptic solution, you have 3mL of the solute, #H_2O_2#.

3% (v/v) is the same thing as writing as #(3mL (H_2O_2))/(100mL(solution)) * 100%# so,

If for every 100mL of soln you have 3mL of #H_2O_2#, then for 348 mL you would have:

#(3mL(H_2O_2) )/(100mL(solution))# = #(x mL)/(348mL (solution))#

#cancel348mL (solution)*(3mL (H_2O_2))/(cancel100mL(solution)) # = #x mL (H_2O_2)#

Answer: 10.44mL #H_2O_2#