What volume (in mL) of #".220 M"# ethanol solution contains #2.90 xx 10^-3# #"mol"# ethanol?

2 Answers
Jun 17, 2017

Answer:

The answer is 13.2 mL.

Explanation:

#"Volume of EtOH" = 2.90 × 10^"-3" color(red)(cancel(color(black)("mol EtOH"))) × "1 L EtOH"/(0.220 color(red)(cancel(color(black)("mol EtOH")))) = "0.0132 L EtOH" = "13.2 mL EtOH"#

Jun 17, 2017

Answer:

#"13.2 mL"#

Explanation:

The idea here is that the molarity of the solution can be converted to the number of moles of solute present in

#"1 L" = 10^3# #"mL"#

of solution. In your case, a #"0.220-M"# solution of ethanol will contain #0.220# moles of ethanol for every #10^3# #"mL"# of solution.

This implies that #2.90 * 10^(-3)# moles of ethanol will be present in

#2.90 * color(blue)(cancel(color(black)(10^(-3))))color(red)(cancel(color(black)("moles ethanol"))) * overbrace((color(blue)(cancel(color(black)(10^3)))color(white)(.) "mL solution")/(0.220color(red)(cancel(color(black)("moles ethanol")))))^(color(blue)("= 0.220 M"))#

# = color(darkgreen)(ul(color(black)("13.2 mL solution")))#

The answer is rounded to three sig figs.