Questions
Which of the following elements has a complete octet of electrons?
- Fluorine
- Oxygen
- Krypton
- Lithium
Which of the following statements is true according to the octet theory?
- During bond formation, the elements have a tendency to acquire unstable configuration.
- During bond formation, the elements merely change their configuration.
- During bond formation, the elements tend to acquire a noble gas configuration.
- None of these
Which of the following pairs will form the most stable ionic bond?
- Na and Cl
- Mg and F
- Li and F
- Na and F
Carbon has 4 valence electrons and an element X has 7 valence electrons. What will be chemical formula of their saturated molecule formed by covalent bonding?
- C4X7
- CX4
- C2X4
- CX7
- C7X4
Among the given compounds H is covalent bonded in case of
- BaH2
- CaH2
- SiH4
- NaH
Which among the following compounds possesses molecules having both covalent and ionic bonds?
- Sodium hydroxide
- Sodium chloride
- Carbon dioxide
- Water
The atomic numbers of four elements A, B, C and D are 6, 8, 10 and 12, respectively. The two elements which can react to form ionic bonds (or ionic compounds) are
- A and D
- B and C
- A and C
- B and D
An ionic bond A+ B– is most likely to be formed when
- the ionisation energy of A is high and the electron affinity of B is low
- the ionisation energy of A is low and the electron affinity of B is high
- the ionisation energy of A and the electron affinity of B is high
- the ionisation energy of A and the electron affinity of B is low
Which of the following options is the best test to distinguish between ionic compounds and covalent compounds?
- Difference in their boiling points
- Solubility
- Conductivity
- None of these
Consider the following statements in respect of covalent compounds:
- They are bad conductors of electricity.
- They are all liquids at room temperature.
- They do not show isomerism.
Which of the statements given above is/are correct?
- Only 1
- Only 1 and 2
- Only 1 and 3
- Only 2
Which of the following are characteristic property/properties of covalent compounds?
- They are hard, crystalline solids.
- They exist as soft solids, liquids or gases.
- They are good conductors of electricity in molten state.
- They are soluble in water.
- They have low melting and boiling points.
- Only 1 and 4
- Only 3 and 5
- Only 1 and 5
- Only 2 and 5
Which of the following have coordinate covalent bonds?
- Br2 and HCl
- Cl2 and F2
- NH4+ and H3O+
- FeCl3 and H2SO4
As compared to covalent compounds, the electrovalent compounds generally have
- high melting point and high boiling point
- low melting point and low boiling point
- low melting point and high boiling point
- high melting point and low boiling point
Which of the following is not a correct difference between electrovalent and covalent compounds?
- Electrovalent compounds have strong electrostatic forces of attraction whereas covalent compounds have weak electrostatic forces of attraction.
- Electrovalent compounds are volatile whereas covalent compounds are non-volatile.
- Electrovalent compounds are good conductors of electricity whereas covalent compounds are non-conductors.
- Electrovalent compounds are soluble in water whereas covalent compounds are insoluble in water.
Which of the following statements is incorrect?
- KCl is soluble in water.
- HCl conducts electricity in its aqueous solution.
- Acetic acid is soluble in water.
- The bond formed between aluminum and fluorine is covalent.