Question

If 0.98 moles of BaCl2 are dissolved in enough water to make a 1.2-liter solution, what is the resulting molarity

Answer 1

Remember that the units of molarity are (moles/liter). You have the number of moles, and you have the number of liters. It becomes division:
(0.98 moles)/(1.2 liters) = 0.82 (moles/liter) = 0.82 M

Answer 2

you just need to divide it

0.98 / 0.12 = 0.816 M

hope this helps