1 The study of chemical equilibrium helps in understanding: A Atomic structure B Reaction yield C Isotopes D Radioactivity
2 Which condition increases the value of equilibrium constant? A Change in pressure B Change in concentration C Change in temperature D Addition of catalyst
3 Increase in temperature favors: A Endothermic reaction B Exothermic reaction C Reverse reaction always D No reaction
4 A catalyst affects equilibrium by: A Changing equilibrium constant B Shifting equilibrium C Increasing rate of both reactions D Stopping reverse reaction
5 Which reaction is endothermic? A Heat is released B Heat is absorbed C No heat change D Always reversible
6 Removal of products shifts equilibrium toward: A Reactants B Products C No change D Stopping reaction
7 Equilibrium constant expression does not include: A Gases B Aqueous solutions C Pure liquids D Products
8 According to the law of mass action, the rate of reaction is proportional to: A Temperature only B Pressure only C Product of active masses of reactants D Volume of container
10 Increase in concentration of reactants shifts equilibrium toward: A Left B Right C No change D Completion
11 Pressure has no effect on equilibrium when: A Reaction is slow B Only solids are involved C Equal moles of gas are present D Catalyst is added
12 At equilibrium, the rate of forward reaction is: A Greater than reverse B Less than reverse C Equal to reverse D Zero
13 Which condition favors formation of more products in exothermic reaction? A Increase temperature B Decrease temperature C Add catalyst D Increase pressure only
14 Which factor affects equilibrium in gaseous reactions only? A Temperature B Pressure C Catalyst D Concentration
15 Which condition is necessary for equilibrium to be established? A Open system B Closed system C High temperature only D Low pressure only
16 According to Le Chatelier’s principle, if stress is applied: A Equilibrium stops B System shifts to reduce stress C System shifts to increase stress D Reaction completes
17 If the equilibrium constant is very small, the reaction favors: A Products B Reactants C Both equally D Completion
20 Equilibrium constant is independent of: A Temperature B Catalyst C Nature of reaction D Stoichiometry
21 Increase in pressure favors the side with: A More moles of gas B Less moles of gas C Equal moles D Solids only
22 When equilibrium is reached, the reaction mixture: A Contains only products B Contains only reactants C Contains both reactants and products D Stops reacting
23 Which of the following is a characteristic of equilibrium? A Occurs in open system B Rate of reaction is zero C Observable properties remain constant D Products stop reacting
24 Which factor does NOT affect the position of equilibrium? A Temperature B Pressure C Concentration D Catalyst
25 Which change will not disturb equilibrium? A Adding more reactant B Removing product C Adding catalyst D Changing temperature
27 Which change shifts equilibrium to the right? A Increase in product concentration B Decrease in reactant concentration C Increase in reactant concentration D Addition of catalyst
29 Chemical equilibrium is important in industry because it: A Stops reactions B Controls product yield C Eliminates catalysts D Prevents reactions
30 Equilibrium constant for a given reaction is: A Always changing B Constant at fixed temperature C Affected by catalyst D Affected by pressure