Chemical equilibrium, Types of Chemical Equilibrium, Change in Concentration, Change in Pressure, Change in Temperature.
Chemical equilibrium occurs in reversible reactions when the rate of the forward reaction equals the rate of the reverse reaction, resulting in a stable state of the system. Dynamic equilibrium, where the forward and reverse reactions continue at the same rate, and static equilibrium, where the overall reaction appears to have stopped while the individual molecular processes continue, are types of chemical equilibrium. Changes in concentration can disrupt equilibrium, visit Nokryan.com.
1. Which of the solution among the following has highest pH?
- 0.01 M NaHCO₃
- 0.1 M H₂SO₄
- 0.02 M CH₃COONa
- 0.01 M NaOH
correct
2. For which system does the equilibrium constant Kc has units of (concentration)¯¹?
- 2HF = H₂ + F₂
- H₂ + 3H₂ = 2NH₃
- 2NO₂ = N₂O₄
correct - H₂ + I₂ = 2HI
3. Which statement about the following equilibrium is correct? 2SO₂(g) + O₂(g) ≈2SO₃(g) ∆H≈ – 188.3 kJmol¯¹
- The value of Kp falls with the rise in temperature
correct - Adding V₂O₅ catalyst increases the equilibrium yield of SO₃
- The value of Kp is equal to Kc
- The value of Kp falls with increasing pressure
4. The pH of buffer solution is 4.74. On adding 0.1 ml (0.00001M) HC1 solution, the pH of solution will be:
- 5.2
- 5.3
- 4.74
correct - 4.7
5. 0.1 M HCI has pH = 1.0, it is about 100 times stronger than acetic acid. Then pH of acetic acid will be:
- 1.3
- 3correct
- 2.0
- 0.1
6. The solubility product of AgCI is 2 x 10¯¹⁰ mol² dm¯⁶. The maximum concentration of Ag⁺ in the solution is:
- 2 x 10¯¹⁰ mol dm¯³
- 1 x 10¯¹⁰ mol dm¯³
- 1.41 x 10¯⁵ mol dm¯³
correct - 2 x 10¯²⁰ mol dm¯³
7. Who studied the effect of temperature on equilibrium?
- Lewis
- Vant Hoff
correct - Arrhenius
- Van der Waal
8. The pH of 10¯³ mol dm ¯³ of an aqueous solution of H₂OS₄ is
- 3.0
- 2.7
correct - 1.5
- 2.0
9. Who introduced the term pH?
- Henderson
- Goldstein
- Sorenson
correct - Thomson
10. Chemical equilibrium involving reactants and products is more than one phase is known:
- Dynamic
- Static
- Heterogeneous
correct - Homogeneous
11. Neutralization of a strong acid with a strong base is:
- None-spontaneous reaction
- Reversible process
- Chemical equilibrium
correct - Spontaneous reaction
12. All of the following are the postulates of Arrhenius theory of ionization except:
- Ionization is reversible process
- Strong electrolyte ionize to a greater extent in water
correct - Electrolyte ionize in water to produce cations and anions
- Electrical conductivity of a solution of an electrolyte depends on the extent to which the electrolyte ionize in solution
13. The value of Kp is greater than Kc for a gaseous reaction when
- Number of molecules of products is greater than those of reactants
correct - Catalyst is added
- Number of molecules of reactants is greater than those of products
- Number of molecules of reactants and products are equal
14. Law of mass action states that rate of chemical reaction is directly proportional to the product of active masses of the reactants. The term active mass means
- Number of moles per dm³ of reactants
correct - Mass in grams converted to products
- Total pressures of the reactants
- Number of moles
15. If the difference of pKa values of the two acids is 2, then:
- Acid with greater pKa is 10 times stronger acid
- Acid with smaller pKa is 10 times stronger acid
- Acid with greater pKa is 100 times stronger acid
- Acid with smaller pKa is 100 times stronger acid
correct
16. The value of Kp is greater than Kc for a gaseous reaction when
- A catalyst is added
- Number of molecules of products is greater than that the reactantscorrect
- Number of molecules of products is greater than the reactants
- Number of molecules of reactants is greater than those of products
17. Le-Chatelier’s principle is applied on the reversible reactions in order to:
- Predict the reaction of reaction
- Determine the rate reaction
- Determine the extent of reaction
- Find the best condition of favorable shifting the position of equilibriumcorrect
18. An excess of aqueous silver nitrate is added to aqueous barium chloride and precipitate is removed by filtration. What are the main ions in the filtrate?
- Ba²⁺ and NO¯₃ only
- Ag⁺ and NO¯₃ only
- Ag⁺ and Ba⁺⁺ and NO¯₃
correct - Ba²⁺ and NO¯₃ and CI¯₃
19. The ionic product of solution is greater than solubility product. The solution is:
- None of all
- Supersaturated
correct - Saturate
- Unsaturated
20. What is the unit of equilibrium constant kc for the following reaction? H₂ + I₂ Ĝ ≈ 2HI
- Mol¯¹ dm³
- None of thesecorrect
- Mol¯² dm³
- Mol dm¯¹
21. The strongest base among the following is
- RbOH
correct - NaCH
- LiOH
- KOH
22. The rate at which a substance reacts is directly proportional to its active mass and the rate of reaction is directly proportional to the product of the active masses of reacting substances in knows as?
- Law of conservation of energy
- Le-Chatelier’s principle
- None of all
- Law of mass action
correct
23. Hydrogen gas and iodine vapours combine to form HI at 425°C. The same composition of mixture is present if we start with decomposition of HI. It suggests.
- A static equilibrium
- A dynamic equilibrium
correct - Irreversible reaction
- Law of mass action
24. Which is not true about buffer is a solution?
- Whose pH is constant
- Which resists change in its pH
- Which resists enough to maintain its pH
- Whose pH may or may not change during a chemical reactioncorrect
25. When rate of forward reaction is equal to rate of backward reaction, then the equilibrium established is called:
- Chemical equilibrium
- Dynamic equilibrium
correct - Static equilibrium
- None of all
Chemistry
- Basic Concepts
- Experimental Techniques
- Gases
- Liquids and Solids
- Atomic Structure
- Chemical Bonding
- Alcohols, Phenols And Ethers
- Solutions
- Chemical Equilibrium
- Electro Chemistry
- Periodic Classification Of Elements & Periodicity
- The Halogens and Noble Gases
- Group III A And IV A Elements
- S-Block Elements
- Fundamental Principles of Organic Chemistry