1st Year Chemistry Chapter 5 Test05. States and Phases of matter

Q1. Multiple choice questions (Attempt all · 10 × 1 = 10)

1. Evaporation causes cooling because:
   1. Molecules absorb energy from surroundings
   2. Molecules release heat
   3. Vapour pressure decreases
   4. Surface area increases
2. Cleavage planes are a property of:
   1. Amorphous solids
   2. Gases
   3. Liquids
   4. Crystalline solids
3. When gases are heated, their:
   1. Volume decreases
   2. Velocity of molecules increases
   3. Density increases
   4. Pressure decreases
4. Which of the following shows hydrogen bonding?
   1. CH4
   2. H2S
   3. H2O
   4. CO2
5. Vapour pressure depends upon:
   1. Temperature
   2. Pressure
   3. Volume only
   4. Density
6. The intermediate phase lying between the solid phase and the normal liquid phase is called;
   1. Crystalline solid
   2. Liquid crystals
   3. Mesogens
   4. Crystal lattice
7. According to kinetic molecular theory, water molecules have low kinetic energy because:
   1. They are far apart
   2. They have strong hydrogen bonding
   3. They are ionic
   4. They move very fast
8. When a solid changes directly into vapour, the process is called:
   1. Condensation
   2. Sublimation
   3. Fusion
   4. Vaporization
9. The melting and freezing of ice are examples of:
   1. Exothermic processes
   2. Endothermic processes
   3. Both a and b
   4. Neutral processes
10. Molar heat of vaporization of water is:
    1. +6.02kJmol⁻¹
    2. +40.7kJmol⁻¹
    3. +22.4kJmol⁻¹
    4. +18.0kJmol⁻¹