Which of the following is not correct regarding the properties of ionic compounds?

• Ionic compounds have high melting and boiling points

• Their reaction velocity in aqueous medium is very high

• Ionic compounds in their molten and aqueous solutions do not conduct electricity

• They are highly soluble in polar solvents

Match the following lists:

List - I	List - II
A. Ethane	1. sp carbons
B. Ethylene	2. 6 sp2 carbons
C. Acetylene	3. 2 sp3 carbons
D. Benzene	4. 2 sp2 carbons 5. 1 sp and 1 sp2 carbons

• A - 3; B - 4; C - 1; D - 2

• A - 4; B - 5; C - 3; D - 2

• A - 3; B - 1; C - 2; D - 5

• A - 2; B - 3; C - 4; D - 5

The number of oxygen atoms bonded to one phosphorous atom in P₄O₆ is

• 4

• 3

• 6

• 5

Which of the following has S - S bond?

• H₂S₂O₆

• H₂S₂O₇

• H₂S₂O₈

• Mustard gas

Which of the following pair of ions have same paramagnetic moment?

• Cu²⁺, Ti³⁺

• Mn²⁺, Cu²⁺

• Ti⁴⁺, Cu²⁺

• Ti³⁺, Ni²⁺

Average C-H bond energy is 416 kJ mol^-1. Which of the following is correct?

• CH₄ (g) + 416 kJ → C (g) + 4H (g)

• CH₄ (g) → C (g) + 4H (g) + 416 kJ

• CH₄ (g) + 1664 kJ → C (g) + 4H (g)

• CH₄ (g) → C (g) + 4H (g) + 1664 kJ

Which of the following is a linear molecule?

• BeCl₂

• H₂O

• SO₂

• CH₄

448.

A molecule (X) has 

(i) four sigma (σ) bonds formed by the overlap of sp² and s orbitals

(ii) one sigma (σ) bond formed by sp² and sp² orbitals and 

(iii) one $\mathrm{\pi }$ bond formed by p_x and p_z orbitals.

Which of the following is X?

• C₂H₆

• C₂H₃Cl

• C₂H₂Cl₂

• C₂H₄

The bond length of HCl molecule is 1.275 Å and its dipole moment is 1.03 D. The ionic character of the molecule (in percent) (charge of the electron = 4.8 × 10^-10 esu) is

• 100

• 67.3

• 33.66

• 16.83

Which one of the following is a correct set ?

• H₂O, sp³, angular

• BCl₃, sp³, angular

• NH${}_4^{+}$, dsp², square planar

• CH₄, dsp², tetrahedral