Question

Which oxide(s) of manganese have a mass percent of the metal that is greater than 50%?MnO MnO2 Mn2O3All of these102

Answer 1

All of these

Step-by-step explanation:

In MnO:

mass of Mn = 55 g (as 1 mole of Mn weighs 55 g)

mass of O = 16 g (as 1 mole of O weighs 16 g)

The mass percent of metal Mn=
`(55)/(55+16)*100=(55)/(71)*100=77.46`

In MnO2:

mass of Mn = 55 g

mass of O = 2*16 = 32 g

The mass percent of metal Mn=
`(55)/(87)*100=63.22`

In Mn2O3:

mass of Mn = 2*55 = 110 g

mass of O = 3*16 = 48 g

The mass percent of metal Mn=
`(110)/(158)*100=69.62`

In all the cases the mass percent of metal is greater than 50.