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Liquid octane reacts with gaseous oxygen gas to produce gaseous carbon dioxide and gaseous water . What is the theoretical yield of carbon dioxide formed from the reaction of of octane and of oxygen gas

User Btbenjamin
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Answer:

24.6g of CO₂ is theoretical yield

Step-by-step explanation:

The reaction of 8.00g of octane with 38.9g of oxygen.

The reaction of octane with oxygen is:

C₈H₁₈(l) + 25/2O₂ → 9H₂O + 8CO₂

1 mole of octane reacts with 25/2 moles of oxygen to produce 8 moles of CO₂

Theoretical yield is the amount of carbon dioxide formed assuming a yield of 100%. To calculate theoretical yield, first, we need to find limiting reactant and, with the chemical reaction, we can obtain the theoretical moles of CO₂ produced and its mass to obtain theoretical yield.

Limiting reactant:

Moles octane (Molar mass: 114.23g/mol) in 8.00g:

8.00g × (1mol / 114.23g) = 0.0700 moles octane.

Moles oxygen (Molar mass: 32g/mol) in 38.9g:

38.9g × (1mol / 32g) = 1.2156 moles oxygen.

For a complete reaction of 1.2156 moles of O₂ there are necessaries:

1.2156 moles O₂ ₓ (1mol C₈H₁₈ / 25/2 moles O₂) = 0.0973 moles octane

As we have just 0.0700 moles,

octane is limiting reactant.

Moles and mass of carbon dioxide:

As limiting reactant is octane, 0.0700 moles of C₈H₁₈ will produce:

0.0700mol C₈H₁₈ × (8 moles CO₂ / 1 mol C₈H₁₈) = 0.56 moles of CO₂ are theoretically produced. In mass (Molar mass CO₂ = 44.01g/mol):

0.56moles CO₂ × (44.01g / mol) =

24.6g of CO₂ is theoretical yield

-Theoretical yield because we are assuming all octane is reacting. In real life, never happens like that-

User Giles Butler
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