Question

What is the molarity of a solution containing 17.0g of nh3 in 2.0 L of solution?

A 0.5m
B 5.0m
C 0.05m
D 0.25m
E 2.0m

Answer 1

to find molarity use the following formula

molarity= moles/ liters

first, we need to calculate the moles using the grams of NH₃. remember to convert grams to moles, you need the molar mass of the molecule which you can determine by adding the mass of each atom

molar mass of NH₃ = 14.0 + (3 x 1.01)= 17.03 g/ mol

now, let convert grams to moles

17.0 g (1 mol/ 17.03 grams)= .998 moles NH₃

now, we can plug in these values to solve for molarity

molarity= 0.998 mol/ 2.0 Liters= 0.50 M (the answer is a)