EQUILIBRIUM

REACTION RATES + ENERGY

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1) The chemical energy of a substance is the sum of the potential and kinetic energy.
What do these energies result from? (P76)
2) What is enthalpy (and its symbol)? (P76)
3) Explain the terms exothermic and endothermic ? use diagrams as an aid (P76)
4) What is ?H? What does it tell us? (P76?77)
5) Give examples of exothermic and endothermic reactions (P77)
6) What is a thermochemical equation? (P77)
7) Write in ?H for the following equations, using the first as a guide
a) CH4(g) + 2O2(g) -->CO2(g) + 2H2O(g) ?H = -890 kJ mol?'
b) 2CH4(g) + 4O2(g) --> 2CO2(g) + 4H2O(g) ?H =
C) CO2(g) + 2H20(g) -->CH4(g) + 2O2(g) ?H =

8) What happens to chemical bonds during a chemical reaction? (P77?78)
9) What is the activation energy? (P78)
10) Draw and describe the energy profiles shown in fig. 8.6 (P78)
11) List and briefly describe the factors that affect the rate of a reaction (P79?80)
(omit catalysts in this question)
12) What is a catalyst? (P8 1) List the two types of catalyst (P82)
13) Explain how catalysts work (P82) ? use the Haber process as an example.
14) How does the energy profile diagram change when a catalyst is used?
15) Attempt Q 8?12, 15,16