Equimolar amounts of gas A and B, each at an initial partial pressure of 1.00 atm are combined in a flask. The flask is sealed and allowed to react to completion according to the reaction:

2A(g)+ B(g) --> C(g)
What is the final pressure inside the flask?

You need the equilibrium constant.

To find the final pressure inside the flask, we need to understand the stoichiometry of the reaction and the ideal gas law.

The stoichiometry of the reaction tells us that 2 moles of gas A react with 1 mole of gas B to produce 1 mole of gas C.

Given that the initial partial pressure of gases A and B are both 1.00 atm, we can assume that the total pressure inside the flask before the reaction is 2.00 atm (1.00 atm for A + 1.00 atm for B).

Since the reaction goes to completion, all of the gases A and B will be consumed to form the product C. Therefore, the final pressure inside the flask will depend on the amount of gas produced, which in this case is gas C.

To determine the final pressure, we need to consider the ideal gas law, which states that PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature.

Since the flask has been sealed and the temperature is kept constant, we can assume that the volume, the number of moles, and the ideal gas constant remain constant throughout the reaction.

We know that initially, we had a total of 2 moles of gas (2 moles of A and 1 mole of B). However, based on the stoichiometry, we would have consumed 2 moles of A and 1 mole of B to produce 1 mole of C. This means that at the end of the reaction, there would only be 1 mole of C left in the flask.

Now, we can use the ideal gas law to calculate the final pressure.
PV = nRT

Since the volume, number of moles, and ideal gas constant are constant, we can write:
P1V = P2V

Where P1 is the initial pressure (2.00 atm) and P2 is the final pressure, and V is the volume.

Since V is constant, we can rewrite the equation as:
P1 = P2

So, the final pressure inside the flask is 2.00 atm.