Answer:
Explanation:
Data Given:
Amount of hydrogen (H₂) = 3.5 g
Oxygen gas (O₂) = 18.7 g
molar mass of H₂O = 18.02 g/mol
molar mass of O₂ = 32 g/mol
molar mass of H₂ = 2.02 g/mol
limiting reactant = ?
Solution:
limiting reactant: The amount of reactant that consume first in a reaction is termed as limiting reagent or limiting reactant.
Excess reagent: the amount of reactant that remain un-reacted at the end of the reaction is termed as excess reagent.
Now to look for the limiting regent we have to look at reaction
Reaction:
2H₂ + O₂ -------> 2H₂O
Convert moles to masses
2H₂ + O₂ -------> 2H₂O
2 mol 1 mol
As we know
molar mass of O₂ = 32 g/mol
molar mass of H₂ = 2.02 g/mol
So we can write it as below
2H₂ + O₂ -------> 2H₂O
2 mol (2 g/mol) 1 mol (32 g/mol)
4 g 32 g
To know with how much hydrogen will react with oxygen apply unity formula
4 g of Hydrogen ≅ 32 g of O₂
g of Hydrogen ≅ 18.7 g of O₂
So,
g of H₂ = 4 g x 18.7 g / 32 g
g of H₂ = 2.33 g
So,
18.7 g of oxygen fully consumed and react with 2.33 g of Hydrogen and 1.16 g of hydrogen remain unreacted.
Oxygen is limiting reactant
From this balance reaction we come to know that 18.7 g of oxygen react with 2.33 g of hydrogen molecule. It means that amount of oxygen is less and it will consume first and act as limiting reactant.
