. The mineral manganosite is a compound of manganese-55 and oxygen-16. If 77% of the mass of manganosite is due to manganese, what is the empirical formula of manganosite?

1 Answer
Nov 5, 2016

Answer:

#"Manganosite"# has an empirical formula of #MnO#

Explanation:

Typically with these problems, we assume a mass of #100*g# of compound, and we work out the empirical formula on this basis.

#"Moles of " ""^55Mn# #=# #(77.0*g)/(55.0*g*mol^-1)# #=# #1.40*mol.#

#"Moles of " ""^16O# #=# #(23.0*g)/(16.0*g*mol^-1)# #=# #1.44*mol.#

These are tolerably close to equimolar quantities, and thus the empirical formula is #MnO#.