Respuesta :
Answer : The correct option is, (A) MnO
Explanation :
As we are given that 77% of the mass of manganosite is due to manganese that means, 77 grams of manganese present in 100 grams of manganosite.
Mass of manganosite = 100 g
Mass of manganese = 77 g
Mass of oxygen = Mass of manganosite - Mass of manganese
Mass of oxygen = 100 g - 77 g
Mass of oxygen = 23 g
Molar mass of Mn = 55 g/mol
Molar mass of O = 16 g/mol
Step 1 : convert given masses into moles.
Moles of Mn = [tex]\frac{\text{ given mass of Mn}}{\text{ molar mass of Mn}}= \frac{77g}{55g/mole}=1.4moles[/tex]
Moles of O = [tex]\frac{\text{ given mass of O}}{\text{ molar mass of O}}= \frac{23g}{16g/mole}=1.4moles[/tex]
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For Mn = [tex]\frac{1.4}{1.4}=1[/tex]
For O = [tex]\frac{1.4}{1.4}=1[/tex]
The ratio of Mn : O = 1 : 1
The mole ratio of the element is represented by subscripts in empirical formula.
The Empirical formula = [tex]Mn_1O_1=MnO[/tex]
Thus, the empirical formula of manganosite is, MnO
