Propane gas (C3H8) burns completely in the presence of oxygen gas (O2) to yield carbon dioxide gas (CO2) and water vapor (H2O). Write a balanced equation for this reaction. Assuming that all volume measurements occur at the same temperature and pressure, how many liters of oxygen will be required to completely burn 0.700 L of propane gas? Assuming that all volume measurements occur at the same temperature and pressure, how many liters of carbon dioxide gas will be produced in the reaction? Assuming that all volume measurements occur at the same temperature and pressure, how many liters of water vapor will be produced in the reaction

These are four questions and four complete answers

Answers:

1) C₃H₈ (g) + 5O₂ (g) → 3CO₂ (g) + 4 H₂O (g)

2) 3.50 liter O₂

3) 2.10 liter CO₂

4) 2.80 liter H₂O

Explanation:

Question 1: Write a balanced equation for this reaction.

1) Word equation (given)

Propane gas (C₃H₈) + oxygen gas (O₂) → carbon dioxide gas (CO₂) + water vapor (H₂O).

2) Chemical equation

C₃H₈ (g) + O₂ (g) → CO₂ (g) + H₂O (g)

3) Balance

Add a 3 coefficient in front of CO₂ on the right side, to balance C:

C₃H₈ (g) + O₂ (g) → 3CO₂ (g) + H₂O (g)

Add a coefficent 4 in front of H₂O on the right side to balance H

C₃H₈ (g) + O₂ (g) → 3CO₂ (g) + 4 H₂O (g)

Add a coefficient 5 in front of O₂ in the left side to balance O:

C₃H₈ (g) + 5O₂ (g) → 3CO₂ (g) + 4 H₂O (g) ← balanced equation

Now all the atoms are balanced (3 carbon atoms, 8 hydrogen atoms, and 10 oxygen atoms, on each side).

Question 2: Assuming that all volume measurements occur at the same temperature and pressure, how many liters of oxygen will be required to completely burn 0.700 L of propane gas?

Since, all volume measurements occur at the same temperature and pressure, you conclude, by ideal gas assumption and Avogadro's principle, that the mole ratios are equal to the volume ratios, and you can use the stoichiometric coefficients given by the chemical equation:

C₃H₈ (g) + 5O₂ (g) → 3CO₂ (g) + 4 H₂O (g)

mole ratio: 1 mol C₃H₈ : 5 mol O₂

Volume ratio: 1 liter C₃H₈ : 5 liter mol O₂

Proportion: 1 liter C₃H₈ / 5 liter mol O₂ = 0.700 liter C₃H₈ / x

x = 0.700 liter C₃H₈ * 5 liter O₂ / 1 liter C₃H₈ = 3.50 liter O₂ ← answer

The answer must show 3 significant figures (3.50).

Question 3. Assuming that all volume measurements occur at the same temperature and pressure, how many liters of carbon dioxide gas will be produced in the reaction?

Based on the same assumptions, ideal gas behavior and Avogadro's principle, use the stoichiometric coefficients given by the chemical equation:

C₃H₈ (g) + 5O₂ (g) → 3CO₂ (g) + 4 H₂O (g)

mole ratio: 1 mol C₃H₈ : 3 mol CO₂

Volume ratio: 1 liter C₃H₈ : 3 liter CO₂

Proportion: 1 liter C₃H₈ / 3 liter mol CO₂ = 0.700 liter C₃H₈ / x

x = 0.700 liter C₃H₈ * 3 liter CO₂ / 1 liter C₃H₈ = 2.10 liter CO₂ ← answer

The answer must show 3 significant figures (2.10)

Question 4. Assuming that all volume measurements occur at the same temperature and pressure, how many liters of water vapor will be produced in the reaction

Based on the same assumptions, ideal gas behavior and Avogadro's principle, use the stoichiometric coefficients given by the chemical equation:

C₃H₈ (g) + 5O₂ (g) → 3CO₂ (g) + 4 H₂O (g)

mole ratio: 1 mol C₃H₈ : 4 mol H₂O

Volume ratio: 1 liter C₃H₈ : 4 liter H₂O

Proportion: 1 liter C₃H₈ / 4 liter mol H₂O = 0.700 liter C₃H₈ / x

x = 0.700 liter C₃H₈*4 liter H₂O / 1 liter C₃H₈ = 2.80 liter H₂O ← answer

The answer must show 3 significant figures (2.80)