Problem 11
Which one of the following compounds liberates \(\mathrm{CO}_{2}\) from aqueous \(\mathrm{NaHCO}_{3} ?\) (a) \(\mathrm{CHCl}_{3}\) (b) \(\mathrm{CH}_{3} \mathrm{Cl}\) (c) Anilinium chloride (d) \(\mathrm{CCl}_{4}\)
Problem 11
Which of the following is chemically inactive allotropic form of carbon? (a) Coal (b) Diamondl (c) Animal charcoal (d) Charcoal
Problem 12
The state of hybridization of ' \(\mathrm{B}^{\prime} \mathrm{BCl}_{3}\) is (a) sp (b) \(\mathrm{sp}^{2}\) (c) \(\mathrm{sp}^{3}\) (d) \(\mathrm{sp}^{3} \mathrm{~d}^{2}\)
Problem 12
Moderate electrical conductivity is shown by: (a) Diamond (b) Carborundum (c) Animal charcoal (d) Charcoal
Problem 13
Borax is not used (a) As a flux in soldering (b) In making enamel and pottery glazes (c) As a styptic to stop bleeding (d) In making optical glasses
Problem 13
Carbon shows tetravalency due to: (a) Dsp \(^{2}\) hybridisation (b) \(\mathrm{Sp}^{3}\) hybridisation (c) \(\mathrm{S}^{2} \mathrm{p}^{2}\) hybridisation (d) \(\mathrm{D}^{3} \mathrm{p}\) hybridisation
Problem 14
Quartz is a crystalline variety of: (a) Silicon (b) Silica (c) Sodium silicate (d) Silicon carbide
Problem 14
The first ionization enthalpies of \(\mathrm{Li}, \mathrm{Be}, \mathrm{B}\) and \(\mathrm{C}\) are given below. Which of these corresponds to Boron? (a) \(520 \mathrm{~kJ} \mathrm{~mol}^{-1}\) (b) \(1086 \mathrm{~kJ} \mathrm{~mol}^{-1}\) (c) \(800 \mathrm{~kJ} \mathrm{~mol}^{-1}\) (d) \(899 \mathrm{~kJ} \mathrm{~mol}^{-1}\)
Problem 15
he metal which does not form ammonium nitrate by reaction with dilute nitric acid is: (a) \(\mathrm{Pb}\) (b) \(\mathrm{Fe}\) (c) \(\mathrm{Mg}\) (d) \(\mathrm{Al}\)
Problem 15
\(\mathrm{BCl}_{3}\) does not exist as dimmer because (a) B has low electronegativity (b) B has small size (c) B has no vacant orbitals (d) B has low electron affinity
