Question

A chemist adds 485 mL of a 0.0025 mol/L calcium sulfate solution to a reaction flask. Calculate the mass in grams of calcium sulfate the chemist has added to the flask. Round your answer to significant digits.

Answer 1

Answer : The mass in grams of calcium sulfate is 0.16 grams.

Explanation :

Molarity : It is defined as the number of moles of solute present in one litre of solution.

Formula used :

$Molarity=\frac{\text{Mass of solute}\times 1000}{\text{Molar mass of solute}\times \text{Volume of solution}}$

Solute is, $CaSO_4$

Given:

Molarity of $CaSO_4$ = 0.0025 mol/L

Molar mass of $CaSO_4$ = 136 g/mole

Volume of solution = 485 mL

Now put all the given values in the above formula, we get:

$0.0025=\frac{\text{Mass of }CaSO_4\times 1000}{136\times 485}$

$\text{Mass of }CaSO_4=0.16g$

Thus, the mass in grams of calcium sulfate is 0.16 grams.