1. Name the geometry of the central oxygen atom in the ozone molecule (O₃).
- 1) Pyramidal
- 2) Tetrahedral
- 3) Linear
- 4) Trigonal planar
Answer: 4)
Explanation: It forms a single bond with one oxygen atom, double bond with another oxygen atom and there exists one more non-bonded atom. Thus, it forms a trigonal planar structure.
2. In which molecule there is a complete linear arrangement of all atoms?
- 1) CH₄
- 2) CO₂
- 3) NH₃
- 4) BF₃
Answer: 2)
Explanation: BF₃ has trigonal planar structure, NH₃ has a trigonal bipyramidal structure, CH₄ has tetragonal structure and hence CO₂ is the one with linear structure.
3. Choose the one which is incorrect
- 1) BeBr₂ - linear
- 2) ClO₄ - tetrahedral
- 3) PF₃ - pyramidal
- 4) BrO₄ - tetrahedral
Answer: 3)
Explanation: PF₃ has a trigonal pyramidal structure as it has three bonding pairs and one non-bonding pair.
4. Which among the following is not a physical property?
- 1) Reactivity
- 2) Solubility
- 3) Boiling point
- 4) Melting point
Answer: 1)
Explanation: Reactivity is a chemical property and it is not a physical property.
5. A crystalline solid possess which one of the following property?
- 1) Non- stability
- 2) Perfect geometric pattern
- 3) Non- symmetric
- 4) Irregularity
Answer: 2)
Explanation: A crystalline solid is one which possesses perfect geometry, high stability, symmetric and regularly arranged.
6. Melting is process which can be stated by the below statements except,
- 1) Change from low temperature to high temperature
- 2) Thermal energy of particles overcome the intercrystalline forces that hold them
- 3) Change from particles in crystal lattice to liquid state
- 4) Change from a highly disordered stated to an ordered state
Answer: 4)
Explanation: Melting is a process which proceeds by changing from a highly ordered state to a disordered state.
7. Which among the following is not associated with intermolecular forces?
- 1) Dipole-dipole interaction and van der Waals forces
- 2) Attraction of oppositely charged particles
- 3) Non- electrostatic in nature
- 4) They hold neutral molecules
Answer: 3)
Explanation: Intermolecular forces are electrostatic in nature.
8. Which among the following statement is not true?
- 1) Boiling involves clubbing of oppositely charged ions
- 2) Thermal energy of particles overcome cohesive forces that hold them
- 3) Boiling involves breaking up of group of molecules in liquid
- 4) In liquid, particles are less regularly arranged and are free to move
Answer: 1)
Explanation: Boiling involves separation of oppositely charged ions and makes them as individual ions.
9. When one of the Hydrogen in Methane( CH₄) is replaced by a hydroxyl group, then structurally methane resembles?
- 1) Both methanol and water
- 2) Water
- 3) Methanol
- 4) Ethanol
Answer: 1)
Explanation: Like water, it is a liquid with boiling point which is abnormally high for a compound of its size and polarity.
10. Which among the following does not match with the term solubility?
- 1) The electrostatic attraction between the oppositely charged ions and their corresponding ends are called ion-dipole bond
- 2) The spaces in between the structures are occupied by solvent molecules
- 3) The ion-dipole bond is very strong
- 4) The structural units get separated from each other
Answer: 3)
Explanation: The bond is weak but in the aggregate they supply enough energy to overcome the interionic forces.
