Question

Calculate the mass in grams of carbon dioxide produced from 11.2 g of octane (C8H18) in the reaction above.

18 + 25 O2 --> 16 CO2 + 18 H2O


89.6 g
17.3 g
34.5 g
46.2 g

Answer 1

34.6g

Step-by-step explanation:

Given parameters:

Mass of Octane = 11.2g

Reaction expression;

2C₈H₁₈ + 25O₂ → 16CO₂ + 18H₂O

Mass of octane = 11.2g

Unknown:

Mass of carbon dioxide produced = ?

Solution:

From the balanced reaction equation;

2 mole of octane produced 16 moles of carbon dioxide

From the given specie, let us find the number of moles;

Number of moles =
`(mass)/(molar mass)`

Molar mass of C₈H₁₈ = 8(12) + 18(1) = 114g/mole

Number of moles of octane =
`(11.2)/(114)` = 0.098mole

2 mole of octane produced 16 moles of carbon dioxide

0.098 mole of octane will produce
`(0.098 x 16)/(2)` = 0.79mole of CO₂

Mass of CO₂ = number of moles x molar mass

Molar mass of CO₂ = 12 + 2(16) = 44g/mol

Mass of CO₂ = 0.79 x 44 = 34.6g