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

If 0.25 moles of H2O are produced, then how many liter (L) of oxygen gas were consumed?
1. 7.00 L
2. 24.4L
3. 28 L

User Nbro
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1 Answer

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Answer: First, we need to use stoichiometry to determine how many moles of oxygen gas were consumed:

From the balanced equation, we can see that for every 4 moles of H2O produced, 5 moles of O2 are consumed. Therefore:

4 mol H2O × (5 mol O2 / 4 mol H2O) = 5 mol O2

So, 0.25 moles of H2O produced will require:

0.25 mol H2O × (5 mol O2 / 4 mol H2O) = 0.3125 mol O2

To convert from moles to liters, we need to use the ideal gas law:

PV = nRT

where P is the pressure, V is the volume, n is the number of moles, R is the gas constant, and T is the temperature. Rearranging the equation to solve for volume, we get:

V = nRT/P

Assuming standard temperature and pressure (STP) of 0°C and 1 atm, we can use R = 0.0821 L·atm/mol·K and P = 1 atm. Substituting the values, we get:

V = (0.3125 mol)(0.0821 L·atm/mol·K)(273 K) / (1 atm) = 6.62 L

Therefore, the answer is not one of the given options. The correct answer is approximately 6.62 L of oxygen gas consumed.

Step-by-step explanation:

User Dasdingonesin
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