If an 11.9*g mass of potassium chloride is dissolved in 256*mL of water, what is the concentration of the solution?

2 Answers
Oct 27, 2017

"0.624 M"

Explanation:

"molarity" = ("moles of solute") / ("liters of solution")

Its units are "mol/L", or simply "M".

Convert "11.9 g KCl" to moles:

11.9 cancel("g KCl") xx ("1 mol KCl") / (74.55 cancel("g KCl")) = "0.160 mol KCl"

Convert milliliters to liters:

"256 mL = 0.256 L"

"molarity" = "0.160 mol" / ("0.256 L") = "0.624 M"

Oct 27, 2017

[KCl(aq)]=0.624*mol*L^-1

Explanation:

"Molarity"="Moles of solute"/"Volume of solution"

And thus we can fill in this quotient....

"Molarity"=((11.9*g)/(74.55*g*mol^-1))/(256*mL*xx10^-3*L*mL^-1)=0.624*mol*L^-1.

Of course, we know in solution there are equimolar K^+ and Cl^-..