Question

Calculate the molarity (m) of a solution prepared by dissolving 10.7 g nai in 0.250 l.

Answer 1

Molarity is defined as the number of moles of solute in 1 L of solution 
number of moles of NaI - 10.7 g / 150 g/mol = 0.0713 mol 
there are 0.0713 mol in 0.250 L
we need to find the number of NaI moles in 1 L
if 0.250 L contains - 0.0713 mol 
then 1 L contains - 0.0713 mol / 0.250 L  = 0.285 mol/L
molarity is 0.285 M

Answer 2

Answer:

0,285M

Explanation:

The molarity of a solution is defined as moles of solute per liter of solution.

If you are dissolving NaI in 0,250L, the NaI is the solute and the volume of the solution is 0,250L.

Knowing molar mass of NaI is 150 g/mol, moles of NaI in 10,7g are:

10,7g × (1mol / 150g) = 0,0713 moles of NaI

As the volume of solution is 0,250L, molarity is:

M = 0,0713 moles of NaI / 0,250L = 0,285M

I hope it helps!