В замкнутом сосуде при температуре 298 К смешали NO и Cl2 в молярном соотношении 2 : 1. Через 5 минут давление в системе оказалось равным 1,28 · 105 Па, а скорость образования NOCl в этом промежутке времени составила 7,5 · 10^(−3) моль/(л · мин). Рассчитайте давление хлора
в исходной смеси.
To start solving this problem, let’s organize the information given and then I’ll provide some guidance on how to approach it:
The reaction taking place is 2 \text{NO} + \text{Cl}_2 \rightarrow 2 \text{NOCl}.
The molar ratio of \text{NO} to \text{Cl}_2 is initially 2:1.
The system is at a temperature of 298 K.
After 5 minutes, the pressure in the system is 1.28 \times 10^5 \text{ Pa}.
The rate of formation of NOCl is 7.5 \times 10^{-3} \text{ mol/(L min)}
Since the formation of NOCl directly affects the number of moles of reactants and the pressure in the system, here is the hint:
Determine the change in the concentration of NOCl over the 5 minutes. This can be done by integrating the rate of formation over the given time interval.
Use stoichiometry to relate the change in concentration of NOCl to the change in concentrations of NO and Cl2.
Understand that the total pressure in a closed system is related to the total number of moles of gases present, based on the Ideal Gas Law: P = (n_{\text{total}}) RT/V .
Remember that the volume V and the temperature T are constants, so the pressure change reflects the mole change.
Now, you can use stoichiometry and the balanced chemical equation to calculate the initial moles (and thus the initial pressure) of Cl2.
As you go through each step, take care to keep units consistent and pay attention to how the stoichiometry of the reaction will affect the consumption of Cl2 relative to the production of NOCl.
Все понял, спасибо большое всем!
Только есть небольшой вопрос, могу ли я приравнять давление газа к его концентрации?
То есть могу ли я скорость реакции приравнять к dp / dt?