Practice Pakistan's most useful MCQs for competitive exams

Formation of vapours from the surface of a liquid is called________________?

• (A)  vapourization
• (B)  evaporation
• (C)  condensation
• (D)  cracking

Answer

Submitted By :Ali Uppal

Water has maximum density at __________________?

• (A)  0°C
• (B)  2°C
• (C)  4°C
• (D)  100°C

Answer

Submitted By :Ali Uppal

The quantity of heat required to convert one mole of liquid into its vapours at its boiling point is called molar heat of__________________?

• (A)  vaporization
• (B)  evaporation
• (C)  crystallization
• (D)  sublimation

Answer

Submitted By :Ali Uppal

Which one is false for evaporation ?

• (A)  Surface phenomenon
• (B)  Continuous
• (C)  Exothermic
• (D)  Cause cooling

Answer

Submitted By :Ali Uppal

When the atoms of third layer are arranged in such a way that they directly lie above the atoms of first layer then this arrangement is called_________________?

• (A)  ABAB (hexagonal)
• (B)  ABCABC (Cubic)
• (C)  Orthor hombic
• (D)  Rhombohedral

Answer

Submitted By :Ali Uppal

Which has strongest bonding in the solid state ?

• (A)  Hydrogen Chloride (HCI)
• (B)  Chlorine (Cl2)
• (C)  Xenon(Xe)
• (D)  Sodium Chloride (NaCI)

Answer

Submitted By :Ali Uppal

All the enthalpy changes are________________?

• (A)  Negative
• (B)  Positive
• (C)  May or may not be A or B
• (D)  none

Answer

Submitted By :Ali Uppal

The pressure during the molar heat of fusion is kept________________?

• (A)  0 atmosphere
• (B)  one atmosphere
• (C)  2 atmosphere
• (D)  10 atmosphere

Answer

Submitted By :Ali Uppal

Isomorphic substances have _______________?

• (A)  Same physical and chemical properties
• (B)  Same physical and different chemical properties
• (C)  Different physical and same chemical properties
• (D)  Different physical and chemical properties

Answer

Submitted By :Ali Uppal

Bucky balls is an allotropic from of__________________?

• (A)  Sulphur
• (B)  Carbon
• (C)  Silica
• (D)  Tin

Answer

Submitted By :Ali Uppal