A dead alkaline battery is found to contain a compound of manganese and oxygen. Its percentage composition is 70.0% Mn and 30.0% O. What is the empirical formula of this substance?

Empirical formula is Mn2O3

Explanation:

Mn = 70.0%

O = 30.0%

Mn = 54.93g/mol

O = 16g/mol

Assume

Mn = 70.0g

O = 30.0g

Mn = 70/54.93 = 1.27

O =   30/16 = 1.875

Divide each by the lower number of moles and round

Mn = 1.27/1.27 = 1

O =   1.875/1.27 = 1.476 so 1.5

Needs to be whole numbers so

Mn = 2

O = 3

Empirical formula is Mn2O3

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."

each  column  of the  table  is called a group. elements in a group share similar properties. groups are  read  from  top  to  bottom. metal. metalloid. nonmetal. solid. liquid. gas. fe. hg. o.  2. 3. 4. 5. 6. 7. 8. 9.  2. beryllium. 9.012. 4.  sodium. 22.990.  11. 3.  magnesium. 24.305.  12.  potassium. 39.098.  19. 4.  calcium. 40.078.  20. i guess  i