Which of the following molecules acts as a Lewis acid?

• (CH)₃B

• (CH₃)O

• (CH₃)P

• (CH₃)P

From the following bond energies:

H-H bond energy: 431.37 kJ mol^-

C=C  bond energy: 606.10 kJ mol-

C- C bond energy: 336.49 kJ mol-

C-H bond energy: 410.50 kJ mol-

Enthalpy for the reaction,


will be

• 1523.6 kJ  mol^-

• -243.6 kJ mol^-

• -1200. kJ mol^-

• -1200. kJ mol^-

Which one of the element with the following outer orbital configuration may exhibit the largest number of oxidation states?

• 3d⁵,4s²

• 3d⁵,4s¹

• 3d⁵,4s²

• 3d⁵,4s²

The ionisation constant of ammonium hydroxide is 1.77 x 10^-5 at 298 K. Hydrolysis constant of ammonium chloride is 

• 5.65 x 10^-10

• 6.50 x 10^-12

• 5.65 x 10^-13

• 5.65 x 10^-13

Oxidation number of P in PO₄^3-, of S in SO₄^2- and that of Cr in Cr₂O₇^2- are respectively,

• +5,+6 and +6

• +3, + 6 and +5

• +5,+3 and +6

• +5,+3 and +6

Amongst the elements with following electronic configuration, which one of them may have the highest ionisation energy?

• [Ne] 3s² 3p³

• [Ne] 3s² 3p²

• [Ar] 3d¹⁰, 4s² 4p³

• [Ar] 3d¹⁰, 4s² 4p³

Maximum number of electrons in a subshell of an atom is determined by the following

• 4l + 2

•  2l +1

• 4l-2

• 4l-2

The values of ΔH and ΔS for the reaction, C_(graphite) + CO₂(g) → 2 CO (g) are 170 kJ and 170 JK^-1 respectively. This reaction will be spontaneous at

• 710 K 

• 910 K

• 1110 K

• 1110 K

Nitrobenzene can be prepared from benzene by using a mixture of conc. HNO₃ and Conc. H₂SO₄.In the mixture, nitric acid acts as a/an:

• reducing agent

• acid

• base

• base

According to MO theory which of the following lists ranks the nitrogen species in terms of increasing bond order?