Question

If you dissolve 25.0 g of NaNO3 (Mm = 85.0 g) in 155 mL of water, what is the molarity of the solution? (Report your answer to two places past the decimal point)​

Answer 1

1.90 M

Step-by-step explanation:

To find the molarity of the solution, you need to use the molarity equation. This formula looks like this:

Molarity (M) = moles / volume (L)

To use this equation, you need to perform some conversions. You should (1) convert mL to L (by dividing by 1,000), then (2) convert grams NaNO₃ to moles (via molar mass), then (3) plug moles and volume into the molarity equation.

155 mL / 1,000 = 0.155 L

25.0 g NaNO₃ 1 mole
--------------------- x ----------------- = 0.294 moles NaNO₃
85.0 g

Molarity = moles / volume

Molarity = 0.294 moles / 0.155 L

Molarity = 1.8975....

Molarity = 1.90 M