Carbon(C):
number of moles= mass/molar mass(Mr)
=65.5/12
=5.5 moles
Hydrogen(H):
number of moles=mass/molar mass (Mr)
=5.5/1
=5.5 moles
Oxygen (O):
number of moles = mass/molar mass (Mr)
=29.0/16
=1.8 moles
EF= lowest number of moles over each of the elements
So,
C= 5.5/1.8 = 3
H= 5.5/1.8 = 3
O= 1.8/1.8 = 1
Therefore Emperical formula= C3H3O
C) Metallic hope this is correct
Answer:
Excess reagent is the ZnS. After the reaction is complete, 1.67 moles of sulfide remain.
Explanation:
This is the reaction to work with:
2ZnS + 3O₂ → 2ZnO + 2SO₂
Limiting reagent is the oxygen. We confirm it by a rule of three
2 moles of sulfide can react to 3 moles of O₂
Therefore 3 moles of ZnS will react to (3 . 3) / 2 = 4.5 moles (we need 4.5 moles of O₂ and we only have 2 moles, that's why the O₂ is the limiting)
Excess reagent is the zinc (II) sulfide
3 moles of oxygen react to 2 moles of ZnS
2 moles of O₂ will react to (2 . 2) / 3 = 1.33 moles of ZnS (it is ok, be cause we have 3 moles, and we need only 1.33)
After the reaction is complete ( 3 - 1.33) = 1.67 moles of sulfide remain.
if you work it put you will get the 3rd one I think
