Exothercy Of Equilibrium

EXPERIMENT 1A ENTHALPY OF DISSOCIATION

Preliminary Questions 1. Define the following terms, both in terms of the overall energy change and in terms of the energies of reactants and products: (a) Exothermic

If a reaction is exothermic, it releases energy when a reaction takes place. The overall energy change is positive as energy is released. ∆H is negative. (b) Endothermic If a reaction is endothermic, it requires energy when a reaction is to take place. The overall energy change is negative as energy is required for a reaction to take place. ∆H is positive.

2. For an exothermic process, how is the equilibrium constant affected by temperature? For an exothermic process, bonds are made. This means at higher temperatures,

Define enthalpy H The amount of energy used by a system at a constant pressure.

EXPERIMENT 1B2 CALORIMETRY

Preliminary Questions

1. What is the difference between heat capacity and specific heat capacity Heat Capacity – The energy to increase the temperature of a system by one degree.

Specific Heat Capacity – Q = m c ∆T where Q = specific heat capacity, m = mass of the object that is having its temperature raised, c = the specific heat capacity of the object being heated and ∆T = the change of temperature.

2. What do you understand in terms of reaction enthalpy ∆rH? Illustrate your answer with an example. The enthalpy change of reaction is the energy change associated with a reaction under standard conditions. E.g. 1 mol dm-3, 1 atm of pressure and 293K. ∆Hr = ∑∆H Reactants - ∑∆H Products

e.g. If total enthalpy of reactants = +221.1 KJ mol-1 and total enthalpy of products = +21.1 KJ mol-1, then reaction enthalpy = +200 KJ mol-1

TERNARY PHASE DIAGRAM Preliminary Questions 1. Define degrees of freedom for multicomponent systems. The degrees of freedom of a system are the number of variables in a system that may be changed without changing the number of phases present at