A 2.89 g sample of a metal chloride, MCl2, is dissolved in water and treated with excess aqueous silver nitrate. The silver chloride that formed weighed 6.41 g. Calculate the molar mass of M. Question 3 options: 70.9 g/mol 29 g/mol 58.0 g/mol 65 g/mol 72.4 g/mol

58.0 g/mol

Explanation:

The reaction that takes place is:

First we calculate how many moles of silver chloride were produced, using its molar mass:

Then we convert AgCl moles into MCl₂ moles, using the stoichiometric ratio:

Now we calculate the molar mass of MCl₂, using the original mass of the sample:

We can write the molar mass of MCl₂ as:

Finally we calculate the molar mass of M:

The closest option is 58.0 g/mol.