Question

The balanced equation for combustion in an acetylene torch is shown below:

2C₂H₂ + 5O₂= 4CO₂ + 2H₂O
The acetylene tank contains 35.0 mol C₂H₂, and the oxygen tank contains 84.0 mol O₂.
How many moles of O₂ are needed to react completely with 35.0 mol C₂H₂?

Answer 1

To react 35.0 mol of C₂H₂ completely, 87.5 mol of O₂ are needed based on the stoichiometry of the balanced equation for the combustion of acetylene.

Step-by-step explanation:

To determine how many moles of O₂ are needed to react completely with 35.0 mol C₂H₂, we will use the stoichiometry of the balanced chemical equation:

2C₂H₂ + 5O₂ = 4CO₂ + 2H₂O

According to the equation, 2 moles of acetylene require 5 moles of oxygen to combust completely. Hence, we calculate the amount of oxygen needed for 35.0 mol C₂H₂:

Number of moles of O₂ needed = (5 moles O₂ / 2 moles C₂H₂) * 35.0 mol C₂H₂

This simplifies to:

Number of moles of O₂ needed = (5/2) * 35.0 mol = 87.5 mol O₂