Question

If 4.74 g of propane is allowed to completely combust, calculate the mass of carbon dioxide formed at the end. Remember the units

Answer 1

14.2g

Step-by-step explanation:

The reaction expression is given as:

C₃H₈ + 5O₂ → 3CO₂ + 4H₂O

Given mass of propane combusted;

4.74g

Unknown:

Mass of carbon dioxide produced = ?

Solution:

To solve this problem, we find the number of moles of the given propane;

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

Molar mass of C₃H₈ = 3(12) + 8(1) = 44g/mol

Number of moles =
`(4.74)/(44)` = 0.11mol

From the balanced reaction equation:

1 mole of C₃H₈ will produce 3 moles of CO₂

0.11mole of C₃H₈ will produce 3 x 0.11 = 0.33mole of CO₂

Mass of CO₂ = number of moles x molar mass

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

Mass of CO₂ = 0.33 x 44 = 14.2g