Question

15 g NiO is dissolved into enough water to make 800. mL of solution. What is the molar concentration of the solution? Report your answer with the correct number of significant figures.

Answer 1

Answer: 0.25

Explanation: M = moles of solute / volume of solution (L)

First, you need to calculate the number of moles using the given mass and the molar mass.

15 g74.692 g/mol≈0.20 mol

Then, you can solve for molarity using the molarity equation. The answer should be reported to two significant figures.

M=0.20 mol/ 0.800 L = 0.25 M