Question

What is the molarity of a solution made by dissolving 4.88 g of KCl in 423 mL of solution?

chemistry molarity

Answer 1

Molarity = `0.154` `M`

Explanation:

mass of `KCl` = `4.88` `g`
molar mass of `KCl` = `74.55` `g`/`mol`
no. of moles = `4.88`g/`74.55` `g`/`mol` = `0.0654` moles
volume of solution = `423 ml` = `0.423L`
Molarity = no. of moles/volume of solution
Molarity = `0.0654` moles/`0.423L`
Molarity = `0.154` `M`

Answer 2

We take the quotient...`"molarity"="moles of solute"/"volume of solution"`

Explanation:

Here........... `"Molarity"=(underbrace((4.88*g)/(74.55*g*mol^-1))_"moles of solute")/underbrace(423*mLxx10^-3L*mL^-1)_"volume of solution"=0.155*mol*L^-1`

And note that the quotient automatically gives the units required for `"concentration".`