Using the following equation, determine the % yield from the following reaction if 30.65 g of octane (C_8 8 ​ H_{18} 18 ​ ) react with excess oxygen to produce 81.75 g of CO_2 2 ​ (g) 2C_8 8 ​ H_{18} 18 ​ (I) + 25O_2 2 ​ (g) → 16CO_2 2 ​ (g) + 18H_2 2 ​ O(l)

Respuesta :

Answer:

The yield of the reaction is 86.11%.

Explanation:

2C₈H₁₈ (l) + 25O₂ (g) → 16CO₂ (g) + 18H₂O (l)

MW C₈H₁₈  = 114 g/mol

1 mol C₈H₁₈  _______ 114 g

       x           _______ 30.65 g

       x = 0.27 mol C₈H₁₈

MW CO₂ = 44 g/mol

1 mol CO₂  _______ 44 g

       x           _______ 81.75 g

       x = 1.86 mol CO₂

Considering a 100% yield reaction:

2 mol C₈H₁₈ ___________ 16 mol CO₂

0.27 mol C₈H₁₈ _________        y

             y = 2.16 mol CO₂

2.16 mol CO₂  _______ 100%

1.86 mol CO₂  _______    z

                 z = 86.11%

Answer:

86.4%

Explanation:

[tex]2C_{8}H_{18} + 25O_{2}->16CO_{2} + 18H_{2}O \\[/tex]

MM (C₈H₁₈) = 12*8+1*18 = 114

MM (CO₂) = 12 + 16*2 = 44

moles of C₈H₁₈ = 30.65 / 114 = 0.269

moles of CO₂ = 81.75 / 44 = 1.860

The % Yield is the amount of a product formed divided by the theorical amount formed if the limiting reactant reacts 100%.

The amount formed of CO₂ is 1.860 moles

The theorical amount formed is obtained with the rule of three and the stoichiometric coefficients.

2 moles of C₈H₁₈ produces 16 moles of CO₂

0.269 moles of C₈H₁₈ produces x moles of CO₂

x = 0.269 * 16 / 2 = 2.152 moles

[tex]\%Yield = \frac{Actual\ amount\ CO_{2}}{Theorical\ amount\ CO_{2}}[/tex]

[tex]\%Yield = \frac{1.860}{2.152} = 0.864 = 86.4%[/tex]