Problem 127
(Me) \({ }_{2} \mathrm{SiCl}_{2}\) on hydrolysis will produce: (a) \((\mathrm{Me})_{2} \mathrm{Si}(\mathrm{OH})_{2}\) (b) \((\mathrm{Me})_{2} \mathrm{~S} \mathrm{i}=\mathrm{O}\) (c) \(-\left[-\mathrm{O}-(\mathrm{Me})_{2} \mathrm{SI}-\mathrm{O}-\right]_{\mathrm{n}}-\) (d) \(\mathrm{Me}_{2} \mathrm{SiCl}(\mathrm{OH})\)
Problem 128
Among the following substituted silanes the one which will give rise to cross linked silicone polymer on hydrolysis is: (a) \(\mathrm{R}_{4} \mathrm{Si}\) (b) \(\mathrm{RSiCl}_{3}\) (c) \(\mathrm{R}_{2} \mathrm{SiCl}_{2}\) (d) \(\mathrm{R}_{3} \mathrm{SiCl}\)
Problem 130
Which of the following statements is incorrect for silicon? (1) Forms an oxide \(\left(\mathrm{SiO}_{2}\right)\) that is amphoteric and has a Ga, As structure. (2) Does not undergo coordination number expasion. (3) Forms strong but unconjugated multiple bonds of the \(\mathrm{p} \pi-\mathrm{d} \pi\) variety, especially with \(\mathrm{O}\) and \(\mathrm{N}\). (4) Forms molecular halides that are not hydrolysed. (a) 2,4 (b) \(1,2,4\) (c) \(1,2,3\) (d) \(2,3,4\)
Problem 131
Which one of the following is correct statement of fullerenes? (a) Fullerenes are made by heating of graphite in an electric arc in the presence of Hydrogen. (b) Fullerenes are the only impure form of carbon due to presence of dangling bonds. (c) It contains twenty six-membered rings and twelve five membered rings. (d) Both (a) and (b).
Problem 132
Which of the following statement is/are correct? (1) \(\mathrm{C}_{60}\) has a geodesic dome structure. (2) Solid \(\mathrm{C}_{60}\) has a cubic close-packed structure. (3) The name buckminsterfullerene was given to \(\mathrm{C}_{60}\) - (4) The common name for \(\mathrm{C}_{60}\) is 'bucky ball' (a) \(1,2,3\) (b) 2,3 (c) \(2,3,4\) (d) \(1,4,3,4\)
Problem 133
What is not a reaction commonly associated with cabondioxide? (a) \(\mathrm{CO}_{2}(\mathrm{~g})+\mathrm{H}_{2} \mathrm{O}(1) \rightleftharpoons\) \(\mathrm{H}+(\mathrm{aq})+\mathrm{HCO}_{3}-(\mathrm{aq})\) (b) \(\mathrm{C}_{6} \mathrm{H} 1_{2} \mathrm{O}_{6}(\mathrm{aq})+6 \mathrm{O}_{2}(\mathrm{~g}) \rightleftharpoons\) \(6 \mathrm{CO}_{2}(\mathrm{~g})+6 \mathrm{H}_{2} \mathrm{O}(\mathrm{l})\) (c) \(\mathrm{CaCO}_{3}(\mathrm{~s})+\) heat \(\rightarrow \mathrm{CaO}(\mathrm{s})+\mathrm{CO}_{2}(\mathrm{~g})\) (d) Oxyhaemoglobin \(+\mathrm{CO}_{2} \rightleftharpoons\) Carboxyhaemoglobin \(+\mathrm{O}_{2}\)
Problem 134
Electrical conductivity in graphite maximized: (a) Perpendicular to the pi frame work and perpendicular to the planar C-atom framework. (b) Parallel to the pi framework and perpendicular to the planar C-atom framework. (c) Parallel to the pi framework and parallel to the planar C-atom framework. (d) Perpendicular to the pi framework and parallel to the planar C-atom framework.
Problem 135
Which of the following statements are correct? (1) The hybridisation of \(\mathrm{C}\) in graphite is \(\mathrm{sp}^{2}\). (2) \(\mathrm{SiO}_{2}\) reacts with \(\mathrm{Na}_{2} \mathrm{CO}_{3}\) and liberates \(\mathrm{CO}\). (3) \(\mathrm{SiO}_{2}\) is used as acid flux. (4) The distance between the layers in graphite is \(3.35 \times 10-3 \mathrm{~cm}\) (a) 1,2 and 3 (b) 1,2 and 4 (c) 1,3 and 4 (d) 2,3 and 4
Problem 136
Which of the following statement is correct for graphite? (1) Its layers are very tightly packed, almost withou tany space between them. (2) It cleaves easily between the layers which acounts for the remarkable softness of the crystals. (3) Its density is lower than that of diamond (4) It has a layered structure and the bonding between the layers is very weak. (a) 2,4 (b) \(1,2,4\) (c) \(1,2,3\) (d) \(2,3,4\)
Problem 137
Which one is correct statement for zeolite? (a) Hydrated zeolites are used as ion exchangers in hardening of soft water (b) ZSM \(-5\) us used to convert gasoline to alcohol (c) They are alumino silicates (d) All of these
