A sample containing 0.187g Cl- is dissolved in 50.0 mL water.

How many moles of Cl- ion are in the solution? (How do I calculate this?)

What is the Molarity of the Cl-iion in the solution? (MCL- = nCl-/Vsoln) (How do I calculate this?

Thanks!
C GIbson

0.187 g of Cl-?

Cl has an atomic weight of 35.453

The units of molecular weight are g/mole. Divide "grams" by "grams/mole" and you end up with moles (just like x divided by x/y yields y).

Molarity = moles per liter "per" implies divide. So you divide the number of moles by the number of liters.