The existence of thermodynamic equilibrium states is a fundamental postulate of thermodynamics. The thermodynamic equilibrium comprises the thermal equilibrium and other forms of equilibrium depending on the type of thermodynamics system. A mechanical system in thermodynamic equilibrium is in thermal equilibrium and in mechanical equilibrium. The internal equilibrium means that there is no heat flows between the various parts of the system so that they all must have the same temperature. All parts of a system in thermal equilibrium have the same temperature. If the object of study is a mechanical system, the thermodynamic equilibrium will also comprise mechanical equilibrium.
1. Equimolar solutions of the following compounds are prepared separately in water. Which will have the lowest pH value?
2. Addition of which chemical will decrease the hydrogen ion concentration of an acetic acid solution?
3. In some solutions, the concentration of H3O+ remains constant even when small amounts of strong acid or strong base are added to them. These solutions are known as
- ideal solution
- colloidal solution
- true solution
- buffer solution
4. All compounds are in equilibrium in a reversible reaction. If reactants are doubled in concentration the equilibrium constant would be
- reduced to half its original value
- reduced to one-fourth of its original value
5. The solubility of Fe(OH)3 would be maximum in
- 0.1M NaOH
- 0.1M HCl
- 0.01M KOH
- 0.1M H2SO4
6. Which of the following sulphides has the largest value of Ksp?
7. According to Le Chatelier’s principle adding heat to a solid and liquid in equilibrium will cause the
- amount of solid to decrease
- amount of liquid to decrease
- temperature to rise
- temperature to fall
8. 0.1M solution of which of the substances will be basic?
- sodium borate
- ammonium chloride
- calcium nitrate
- sodium sulphate
9. At a certain temperature 2HI ⥨ H2 + I2 only 50% HI is dissociated at equilibrium. The equilibrium constant is
10. Which has the highest degree of ionization?
- 0.1M NH3
- 0.001M NH3
- 0.1M NH3
- 0.0001M NH3