Question

C3H8 + 5 O2 → 3 CO2 + 4 H2O

Answer 1

Answer:

Mass = 112 g

Explanation:

Given data:

Mass of CO₂ produced = 90.6 g

Mass of oxygen needed = ?

Solution:

Chemical equation:

C₃H₈ + 5O₂       →      3CO₂+ 4H₂O

Number of moles of CO₂:

Number of moles = 90.6 g/ 44 g/mol

Number of moles = 2.1 mol

Now we will compare the moles of  CO₂ and oxygen:

                 CO₂           :           O₂

                    3             :            5

                    2.1           :        5/3×2.1 = 3.5

Mass of oxygen needed:

Mass = number of moles × molar mass

Mass = 3.5 mol × 32 g/mol

Mass = 112 g