A sample of NaNo3 weighing 0.38g is placed in 50.0mL volumetric flask. The flask is then filled with water to the mark on the neck, dissolving the solid. What is the molarity of the resulting solution.

0.0894 M

Explanation:

So you first want to change the grams into moles (since molarity is moles solute per Liter solution).

The molar mass of NaNO3 is 84.995 g/mol, so we divide 0.38g of NaNO3 by 84.995 g/mol to get approximately 0.004471 mol NaNO3.

Now, all you have to do is to divide by the total Liters of water (your solution).

Since the volume is expressed in mL, you just need to divide by 1000 (1 L = 1000mL) to get 0.050 L solution.

Therefore, to get molarity, you divide 0.004471 mol by 0.050 L to get your answer of 0.0894 M.