A chemist prepares a solution of mercury (I) chloride Hg2Cl2 by measuring out

0.000126 μmol of mercury (I) chloride into a 100. mL volumetric flask and filling the flask to the mark with water.

Calculate the concentration in mmol/L of the chemist's mercury (I) chloride solution.

Round the answer to three significant figures.

1.26 * 10^-8 M

Explanation:

We are given;

Number of moles of mercury (i) chloride as 0.000126 μmol

Volume is 100 mL

We are required to calculate the concentration of the solution.

We need to know that;

Concentration is also known as molarity is given by;

Molarity = Number of moles : Volume

Number of moles = 1.26 * 10^-10 Moles

Volume = 0.01 L

Therefore;

Concentration = 1.26 * 10^-10 Moles : 0.01 L

= 1.26 * 10^-8 M

Thus, the molarity of the solution is 1.26 * 10^-8 M