The complete combustion of propane (C3H8) in the presence of oxygen yields CO2 and H2O:
C3H8 (g) + 5O2 (g) 3CO2 (g) + 4H2O (g)
a. Calcluate the volume of carbon dioixde ( at s.t.p.) that would be produced by the
combustion of 27.5 g of C3H8 burns in the presence of 45.0 L of O2.

Respuesta :

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Answer:

[tex]\large \boxed{\text{27.0 L CO}_{2}}[/tex]

Explanation:

We are given the amounts of two reactants and asked to determine the amount of product.

This is a limiting reactant problem.

1. Assemble the information

We will need a balanced chemical equation with molar masses and volumes, so, let's gather all the information in one place.

MV/L:                    22.71    22.71

Mᵣ:             44.10

                  C₃H₈ + 5O₂ ⟶ 3CO₂ + 4H₂O

m/g:            27.5

V/L:                        45.0

2. Calculate the moles of each reactant

(a) Propane

[tex]\text{Moles of C$_{3}$H$_{8}$} = \text{27.5 g C$_{3}$H$_{8}$} \times \dfrac{\text{1 mol C$_{3}$H$_{8}$}}{\text{44.10 g C$_{3}$H$_{8}$}} = \text{0.6236 mol C$_{3}$H$_{8}$}[/tex]

(b) Oxygen

The volume of 1 mol of a gas at STP (0 °C and 1 bar) is 22.71 L

[tex]\text{Moles of O$_{2}$} = \text{45.0 L O}_{2} \times \dfrac{\text{1 mol O$_{2}$}}{\text{22.71 L O$_{2}$}} = \text{1.982 mol O$_{2}$}[/tex]

3. Calculate the moles of CO₂ from each reactant

[tex]\textbf{From C$_{3}$H$_{8}$:}\\\text{Moles of CO$_{2}$} = \text{0.6236 mol C$_{3}$H$_{8}$} \times \dfrac{\text{3 mol CO$_{2}$}}{\text{1 mol C$_{3}$H$_{8}$}} = \text{1.871 mol CO}_{2}\\\\\textbf{From O$_{2}$:}\\\text{Moles of CO$_{2}$} =\text{1.982 mol O$_{2}$} \times \dfrac{\text{3 mol CO$_{2}$}}{\text{5 mol O$_{2}$}} = \text{1.189 mol CO$_{2}$}\\\\\textbf{Oxygen} \text{ is the limiting reactant because it gives fewer moles of CO$_{2}$.}[/tex]

4. Calculate the volume of CO₂

[tex]\text{ Volume of CO$_{2}$} = \text{1.189 mol CO$_{2}$} \times \dfrac{\text{22.71 L CO$_{2}$}}{\text{1 mol CO$_{2}$}} = \textbf{27.0 L CO}_\mathbf{{2}}\\\\\text{The reaction produces $\large \boxed{\textbf{27.0 L CO}_\mathbf{{2}}}$}[/tex]