Question

calculate the molar mass of a metal that forms an oxide having the empirical formula M2O3 and contains 68.04% of the metal by mass. identify the metal.

Answer 1

Answer:

51.094 g/mol

Explanation:

We are given;

• Empirical formula as M2O3
• Percentage of metal M by mass is 68.04%

We are required to determine the molar mass of M

Step 1: Determine the percentage by Mass of Oxygen in the compound

% by mass of Oxygen = 100% -68.04%

                                   = 31.96%

Step 2: Mass of M in the compound

Mass of oxygen in the compound = 16.0 g × 3 atoms

                                                        = 48.0 g

Therefore; 48.0 g is equivalent to 31.96% of the compound.

Thus; 68.04 % will be equivalent to a mass of ;

= (48.0 g × 68.04%) ÷ 31.96%

= 102.188 g

Step 3: molar mass of M

Mass of M in the compound is 102.188 g

But there are two atoms of M in the compound

Therefore; Molar mass of M = 102.188 g ÷ 2

                                              =51.094 g

Thus, the molar mass of M is 51.094 g/mol