Skip to content
MathsGenie logo
Open app

Course home

  1. A Level
  3. Chemistry OCR A
  5. Question bank

Rates, equilibrium and pH

EasyMediumHard
1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162
Question 55

The reaction between nitrogen monoxide, NO(g)\text{NO}(\text{g})NO(g), and oxygen, O2(g)\text{O}_2(\text{g})O2​(g), forms nitrogen dioxide, NO2(g)\text{NO}_2(\text{g})NO2​(g), according to the following equilibrium:

2NO(g)+O2(g)⇌2NO2(g) 2\text{NO}(\text{g}) + \text{O}_2(\text{g}) \rightleftharpoons 2\text{NO}_2(\text{g}) 2NO(g)+O2​(g)⇌2NO2​(g)

An industrial scientist carries out research into this equilibrium:

  • The chemist fills a 8.4 dm38.4\text{ dm}^38.4 dm3 container with NO(g)\text{NO}(\text{g})NO(g) at room temperature and pressure (RTP), and then adds 9.60 g9.60\text{ g}9.60 g of O2(g)\text{O}_2(\text{g})O2​(g). (Assume 1 mol1\text{ mol}1 mol of gas occupies 24.0 dm324.0\text{ dm}^324.0 dm3 at RTP).
  • The mixture is heated with a catalyst and allowed to reach equilibrium at a total pressure of 3.00 atm3.00\text{ atm}3.00 atm and a temperature of 800 K800\text{ K}800 K.
  • A sample of the equilibrium mixture is analysed and found to contain 0.260 mol0.260\text{ mol}0.260 mol of NO2(g)\text{NO}_2(\text{g})NO2​(g).
a.

Write an expression for KpK_{\text{p}}Kp​ for this equilibrium, including its units.

[2]
b.

Determine the value of KpK_{\text{p}}Kp​ at 800 K800\text{ K}800 K. Show your working and give your answer to 3 significant figures.

[6]

Rates, equilibrium and pH Questions

  1. A Level
  2. /Chemistry
  3. /Rates, equilibrium and pH