70. Solving a chemistry problem

2. For a chemical reaction of a given option (Table 6.1):
1) derive an analytical dependence of the change in heat capacity on temperature ∆Cp = f(T), calculate ∆Cp at 5 temperatures (K): 298, the temperature T indicated in the table and three temperatures taken from the interval (298÷T); according to the data obtained, plot the dependence ∆Ср = f(T);
2) calculate the change in enthalpy (heat effect of the reaction at P = const) from the heats of formation of substances, the change in entropy, the change in Gibbs free energy under standard conditions (∆Ho298, ∆So298, ∆Go298);
3) derive an analytical dependence of the change in enthalpy on temperature ∆HoT = f(T), calculate the change in enthalpy at the same temperatures as indicated in paragraph 1, plot the dependence ∆HoT = f(T);
4) calculate ∆S0T ; ∆G0T at a given temperature T;
5) calculate the equilibrium constant (Ko) at a temperature of 298 K and at a given temperature T.
Based on the calculations carried out, the following conclusions can be drawn:
1) what kind of reaction is it - exo- or endothermic (heat is released or absorbed during the reaction);
2) how temperature affects the thermal effect of the reaction;
3) in which direction is the chemical equilibrium shifted;
4) how temperature affects the equilibrium position;
5) how pressure affects the equilibrium position.
Conclusions must be substantiated with the involvement of relevant laws.
When calculating, the phase state of the substances participating in the chemical reaction must be taken into account (the phase state of individual substances is indicated in Table 6.1, the rest of the substances are taken to be in a gaseous or liquid state).
Table 6.1
Option Chemical reaction Options for key temperatures (T, K)
1 2 3
2 H2 Cl2 = 2 HCl 400 800 1300