Unit 3- Calculating And Explaining Energy Change Flashcards
What 2 things will change the position of the equilibrium?
Altering temperature and pressure
What will raising temperature do to a reversible reaction? What will raising the pressure do?
Raising temperature will increase the endothermic reaction
Raising pressure will increase the reaction that produces less volume
What is the haber process?
The industrial process of making ammonia
What is the equation for making ammonia?
N2 + 3H2 2NH3 (+ heat)
Why is the temperature only raised to 450 degrees?
Increasing too much favours the backward reaction but 450 increases rate of reaction
Explain the haber process?
H2 and N2 passed through tank with trays of iron catalyst, reaches condenser leaving liquid ammonia at bottom to be drained and hydrogen and nitrogen to be reused
How do you measure the energy released in a reaction?
Mix substances in polystyrene cup measure temp before and after
What type of reaction is bond breaking? Bond forming?
Breaking: endothermic
Forming: exothermic
What does a calorimetry do?
Calculates energy released from fuel
How do you carry out a calorimetry experiment?
50g in copper pot record temperature, weigh spirit burner, put spirit burner below pot measure temperature up to 50 degrees then measure weight of spirit burner
Mass of water x specific heat capacity of water (4.2) x temperature change equals …….
Energy transferred
What is the energy change in an exothermic reaction? And endothermic?
Exo: Negative
Endo: positive
What is the initial rise in bond energy graphs?
The activation energy
What does a catalyst do to the activation energy?
Lowers
What are combustion engines?
Very cleans motor engines that just emit water vapour
