Question

When 0.054 moles of aluminum sulfate are
dissolved in enough water to make 459
milliliters of solution, what is the molarity
of sulfate ions?
Answer in units of M.

Answer 1

Molarity = moles of solute (aluminum sulfate) divided by the volume of the solution in L. So, to calculate the molarity, divide the moles of aluminum sulfate by the volume of solution in L.

Answer 2

\[\sf \frac{0.054 ~mol~Al_2(SO_4)_3}{459~mL~soln}~\times ~ \frac{1~mL}{10^{-3}~L~ soln}~\times \frac{3~mol~SO_4^{2+}~ions}{1~mol~Al_2(SO_4)_3}\]\[\sf=\frac{(0.054 \cdot 3)~ mol~ SO_4^{2+} ~ions}{(459 \cdot 10^{-3}) ~L~ soln} \]\[=~?\]

Answer 3

.4 or .35 or .353 ??? depending on what you used for sig figs? @Jhannybean

Answer 4

The answer I got was: \[\sf \frac{0.35 ~mol~ SO_$^{2+}~ions }{1~L~soln}\] 2 sig figs because you started with 0.054 moles aluminum sulfate

Answer 5

thanks so much!!!!