Question

When 25.4 g NaNO3 is dissolved in water to make 1250 mL of solution, what is the molarity of the solution?

Answer 1

Answer:

Molarity = 0.24 mol/L

Explanation:

Given data:

Mass of NaNO3 = 25.4 g

Volume of solution = 1250 mL

Molarity = ?

Solution:

Molarity of solution is equal to the number of moles of solute divided by volume of solution in litter.

Formula:

Molarity = number of moles / volume in L

First of all we will convert the volume in litter.

1 L = 1000 mL

1250 / 1000 = 1.25 L

Now we calculate the moles of NaNO3 in present in 25.4 g.

Number of moles = mass / molar mass

Molar mass of NaNO3 = (23 + 14+ 16×3) = 85 g/mol

Number of moles =  25.4 g / 85 g/mol

Number of moles = 0.299 mol

Now we will calculate the molarity of solution

Molarity = number of moles / volume in L

Molarity = 0.299 mol / 1.25 L

Molarity = 0.24 mol/L