When 1.0 atm of CO gas reacts completely to form carbon suboxide at 550°C, what is the final pressure in the container?

• A. 0.00 atm
• B. 0.10 atm
• C. 0.25 atm
• D. 0.50 atm

Answer: (D)

To determine the final pressure in the container after the reaction, we first need to consider the reaction taking place and how the moles of gas change as a result.

When CO gas reacts to form carbon suboxide, it can be represented by the following balanced chemical reaction:

[ 2 \text{CO} \rightarrow \text{C}_3\text{O}_2 + \text{other products} ]

In this reaction, 2 moles of CO gas produce 1 mole of carbon suboxide. This means that for every 2 moles of CO consumed, only 1 mole of product is formed. Therefore, the total number of moles of gas decreases during the reaction.

Given that we start with 1.0 atm of CO, we need to consider how the number of moles changes. If 1.0 atm of CO is completely reacted, we can evaluate how the partial pressures relate to the final condition of the system.

Since 2 moles of CO yield 1 mole of carbon suboxide, we see a reduction in gas moles. The initial pressure represents 1.0 atm from CO, and when it completely reacts, the pressure in terms of moles of gas reduces:

1