Chemistry - Thermochemistry

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Question - 1

Consider the following statements

1. kinetic energy in the energy of motion.

2. Potential energy is stored energy.

3. Fuel gases (as LPG) contain potential energy in their chemical bonds.

Which of the above is/are correct?

  • A Only 1
  • B Only 2
  • C 1,2 and 3
  • D None of the above

Question - 2

An increase in temperature increases which of the following?

1. The rate constant of a reaction

2. The ionic product of water

3. The equilibrium constant of an exothermic reaction.

Select the correct answer using the codes given below.

  • A 1 and 2 only
  • B 2 and 3 only
  • C 1 and 3 only
  • D All of the above

Question - 3

If a refrigerator's door is kept open, then

  • A room will be cooled
  • B room will be heated
  • C room may get cooled or heated depending upon the weather
  • D No effect

Question - 4

A fan produces a feeling of comfort during hot weather, because

  • A our body radiates more heat in air
  • B fan supplies cool air
  • C conductivity of air increases
  • D our perspiration evaporates rapidly

Question - 5

Which of the following is a closed system?

  • A Jet engine
  • B Tea placed in steel kettle
  • C Pressure cooker
  • D Rocket engine during propulsion

Question - 6

Match Column I with  Column II.

Column I Column II
A. Endothermic 1. Variation of enthalpy of a reaction temperature
B. EXothermic 2. A process or reaction which consumes heat
C. Activation energy 3. A process or reaction that releases heat
D. Arrhenius equation 4. The amount of energy which must be invested in a reaction to get it started

Select the correct answer using the codes given below.

  • A A B C D 2 3 4 1
  • B A B C D 3 4 1 2
  • C A B C D 4 1 2 3
  • D A B C D 1 2 3 4

Question - 7

In the pressure cooker, cooking is faster because the increase in vapour pressure

  • A increases the specific heat
  • B decreases the specific heat
  • C decreases the boiling point
  • D increases the boiling point

Question - 8

Assertion (A) When H2O is added to CaO, heat is liberated.

Reason (R) Reaction between CaO and H2O is exothermic.

  • A Both A and R are individually true and R is the correct explanation of A
  • B Both A and R are individually true, but R is not the correct explanation of A
  • C A is true, but R is false
  • D A is false, but R is true

Question - 9

If a system A is in thermal equilibrium with B and B is in thermal equilibrium with C, then A and C are in equilibrium with other. "This is a statement of"

  • A cyclic rule
  • B zeroth law of thermodynamics
  • C first law of thermodynamics
  • D second law of thermodynamics

Question - 10

A close bottle containing water at room temperature was taken to the moon and then the lid is opened. The water will

  • A freeze
  • B boil
  • C decompose into oxygen and hydrogen
  • D not change at all