Question

Which of the following compounds has the highest mass percent of "O"?Group of answer choicesMnO2MnOnone of the aboveMn2O3Mn3O2

Answer 1

Among the given manganese compounds, MnO₂ has the highest mass percent of oxygen, calculated to be 36.80%. Percent composition calculations for each compound showed that MnO₂ contains the greatest proportion of oxygen by mass.

Step-by-step explanation:

To determine which compound has the highest mass percent of oxygen (O), we calculate the percent composition of oxygen in each compound. The percent composition is found by dividing the total mass of oxygen in the compound by the molar mass of the compound and multiplying by 100.

• MnO₂: Molar mass is 54.94 g/mol (Mn) + 32.00 g/mol (O₂) = 86.94 g/mol. Oxygen mass percent = (32/86.94)*100 = 36.80%.
• Mn₂O₃: Molar mass is 2*54.94 g/mol (Mn) + 48.00 g/mol (O₃) = 157.88 g/mol. Oxygen mass percent = (48/157.88)*100 = 30.40%.
• Mn₃O₄: This is the empirical formula for MnO. Its molar mass is 3*54.94 g/mol (Mn) + 16.00 g/mol (O) = 180.82 g/mol. Oxygen mass percent = (16/180.82)*100 = 8.85%.

Adding to our options, MnO is not on the initial list but let's calculate it for completeness: MnO has a molar mass of 54.94 g/mol (Mn) + 16.00 g/mol (O) = 70.94 g/mol. Oxygen mass percent = (16/70.94)*100 = 22.56%.

Comparing the oxygen mass percent for all these compounds, MnO₂ has the highest mass percent of O at 36.80%.

Answer 2

Which of the following compounds has the highest mass percent of "O"?

MnO₂ MnO Mn₂O₃ Mn₃O₂

To solve the problem we will find the percenta mass of O that each compound has. To do that, we will suppose that we have 1 mol of each and find the mass of that mol, and the mass of O. To find the molar mass of them, we have to look for the atomic masses of Mn and O in the periodic table, they are:

Mn: 54.94 amu

O: 1