Problem 1
\(\mathrm{BCl}_{3}\) is a planar molecule because in this molecule boron is (a) sp \(^{2}\)-hybridized (b) sp-hybridized (c) sp \(^{3}\)-hybridized (d) sp^{3} d - h y b r i d i z e d ~
Problem 2
In diborane (a) 2-bridged hydrogens and four terminal hydrogens are present (b) 3-bridged hydrogens and three terminal hydrogens are present (c) 4-bridged hydrogens and two terminal hydrogens are present (d) none of the above
Problem 3
Which one of the following boron compounds is optically active? (a) boron anhydride (b) sodium tetraborate (c) borosalicylic acid (d) boron trifluoride
Problem 4
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 5
Which of the following compounds are formed when \(\mathrm{BCl}_{3}\) is treated with water? (a) \(\mathrm{B}_{2} \mathrm{O}_{3}+\mathrm{HCl}\) (b) \(\mathrm{H}_{3} \mathrm{BO}_{3}+\mathrm{HCl}\) (c) \(\mathrm{B}_{2} \mathrm{H}_{6}+\mathrm{HCl}\) (d) none of these
Problem 6
Which of the following is the strongest Lewis acid? (a) \(\mathrm{BBr}_{3}\) (b) \(\mathrm{BCl}_{3}\) (c) \(\mathrm{BI}_{3}\) (d) \(\mathrm{BF}_{3}\)
Problem 8
Which of the following reacts with \(\mathrm{BCl}_{3}\) to form diborane? (a) \(\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}\) (b) \(\mathrm{NH}_{3}\) (c) \(\mathrm{NaHg}\) (d) \(\mathrm{LiAlH}_{4}\)
Problem 9
In the reaction \(\mathrm{B}_{2} \mathrm{H}_{6}+2 \mathrm{KOH}+2 \mathrm{X} \longrightarrow 2 \mathrm{Y}+6 \mathrm{H}_{2}\) \(\mathrm{X}\) and \(\mathrm{Y}\) are respectively (a) \(\mathrm{HCl}, \mathrm{KBO}_{3}\) (b) \(\mathrm{H}_{2}, \mathrm{H}_{3} \mathrm{BO}_{3}\) (c) \(\mathrm{H}_{2} \mathrm{O}, \mathrm{KBO}_{2}\) (d) \(\mathrm{H}_{2} \mathrm{O}, \mathrm{KBO}_{3}\)
Problem 10
Reactivity of borazole is greater than that of benzene because (a) it has localized electron in it (b) borazole is electron deficient compound (c) borazole is polar compound (d) borazole is non-polar compound
Problem 11
In diborane, the two \(\mathrm{H}-\mathrm{B}-\mathrm{H}\) angles are nearly (a) \(60^{\circ}, 120^{\circ}\) (b) \(95^{\circ}, 150^{\circ}\) (c) \(95^{\circ}, 120^{\circ}\) (d) \(120^{\circ}, 180^{\circ}\)
