West Bengal Police Constable Special Mock Test

Chemistry - Chemical Reaction

1 / 10

1) In a reaction between hydrochloric acid and sodium hydroxide, what is the role of water in the reaction?

A) Water is an inhibitor of the reaction.

B) Water is a reactant in the reaction.

C) Water acts as a catalyst.

D) Water is a product of the reaction.

2 / 10

2) Which of the following statements is true for an isolated system in equilibrium?

A) The concentration of products increases over time.

B) The forward reaction stops completely.

C) The rate of the forward reaction equals the rate of the reverse reaction.

D) The concentration of reactants decreases over time.

3 / 10

3) In a chemical equilibrium, what happens when the concentration of products is increased?

A) The equilibrium shifts towards the reactants.

B) The reaction stops immediately.

C) The equilibrium shifts towards the products.

D) The equilibrium remains unchanged.

4 / 10

4) Which of the following reactions demonstrates the law of conservation of mass?

A) Dissolving sugar in water where the mass of the solution is less than the sum of sugar and water.

B) Burning coal in the presence of oxygen where the mass of the resulting gases is equal to the mass of coal plus oxygen.

C) Electrolysis of water into hydrogen and oxygen where the mass of the gases is less than the original water.

D) Combining hydrogen and nitrogen to form ammonia where the mass of ammonia is greater than the sum of hydrogen and nitrogen.

5 / 10

5) In an endothermic reaction, which of the following energy changes occurs?

A) Energy is conserved in the form of heat

B) Energy is absorbed from the surroundings

C) There is no net energy change

D) Energy is released into the surroundings

6 / 10

6) What is the role of a catalyst in a chemical reaction?

A) It increases the equilibrium constant

B) It changes the thermodynamics of the reaction

C) It gets consumed in the reaction

D) It decreases the activation energy

7 / 10

7) In an exothermic reaction, which of the following statements is true about the enthalpy change?

A) The enthalpy change is zero, indicating no heat transfer.

B) The enthalpy change is positive, and heat is absorbed.

C) The enthalpy change is unpredictable.

D) The enthalpy change is negative, and heat is released.

8 / 10

8) Which type of chemical reaction is represented by the equation: 2KClO3(s) → 2KCl(s) + 3O2(g)?

A) Displacement reaction

B) Double displacement reaction

C) Decomposition reaction

D) Combination reaction

9 / 10

9) In the context of a chemical reaction, what does the term 'enthalpy' refer to?

A) The total heat content of a system

B) The activation energy required for a reaction

C) The randomness or disorder of a system

D) The pressure-volume work done by a system

10 / 10

10) Why do reactions tend to proceed at a faster rate in solutions than in the solid state?

A) The increased pressure in solutions

B) The larger surface area in solutions

C) The higher concentration of reactants in solutions

D) The greater freedom of movement of molecules in solutions

Your score is

Curriculum

Chemistry (Chemical Reaction রাসায়নিক বিক্রিয়া)

Report a question

Modal title