Problem 74
When strongly heated, orthoboric acid gives (a) \(\mathrm{H}_{2} \mathrm{~B}_{4} \mathrm{O}_{7}\) (b) \(\mathrm{B}_{2} \mathrm{O}_{3}\) (c) \(\mathrm{HBO}_{2}\) (d) \(\mathrm{NaBO}_{2}+\mathrm{B}_{2} \mathrm{O}_{3}\)
Problem 74
A pseudo solid is: (a) Glass (b) \(\mathrm{CaCO}_{3}\) (c) Rock salt (d) Diamond
Problem 75
The number of carbon compound is very large because: (a) It has strong catenation property (b) It shows allotropy (c) It has non metallic character (d) Carbon is tetravalent
Problem 75
In the reaction: \(\mathrm{Al}_{2}\left(\mathrm{SO}_{4}\right)_{3} .18 \mathrm{H}_{2} \mathrm{O} \frac{\text { heat }}{-18 \mathrm{H}_{2} \mathrm{O}}\) \(\mathrm{A} \quad{ }_{90^{\circ} \mathrm{C}}{\longrightarrow} \mathrm{B}+\mathrm{C}\). The product \(\mathrm{A}, \mathrm{B}\) and \(\mathrm{C}\) are respectively (a) \(\mathrm{Al}_{2}\left(\mathrm{SO}_{4}\right)_{3}, \mathrm{Al}_{2} \mathrm{O}_{3}, \mathrm{SO}_{3}\) (b) \(\mathrm{Al}_{2} \mathrm{O}_{3}, \mathrm{Al}_{2}\left(\mathrm{SO}_{4}\right)_{3}, \mathrm{SO}_{3}\) (c) \(\mathrm{Al}_{2} \mathrm{SO}_{4}, \mathrm{Al}_{2} \mathrm{O}_{3}, \mathrm{SO}_{3}\) (d) \(\mathrm{Al}_{2}\left(\mathrm{SO}_{4}\right)_{3}, \mathrm{Al}_{2} \mathrm{O}_{3}, \mathrm{SO}_{2}\)
Problem 76
In graphite, electrons are: (a) Spread out between the structure (b) Localized on earth C-atom (c) Present in anti-bonding orbital (d) Localized on every third C-atom
Problem 77
What is \(\mathrm{X}\) in the following reaction? \(\mathrm{SiCl}_{4}+\mathrm{H}_{2} \mathrm{O} \rightarrow \mathrm{X}+\mathrm{HCl}\) (a) \(\mathrm{H}_{4} \mathrm{SiO}_{4}\) (b) \(\mathrm{SiH}_{4}\) (c) \((\mathrm{SiOOH})_{2}\) (d) \(\mathrm{Si}\left(\mathrm{ClO}_{4}\right)_{4}\)
Problem 77
In the reaction \(\mathrm{B}_{2} \mathrm{H}_{6}+2 \mathrm{KOH}+2 \mathrm{X} \rightarrow 2 \mathrm{Y}+6 \mathrm{H}_{2}\) \(\mathrm{X}\) 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 78
\(\mathrm{X}\) reacts with aqueous \(\mathrm{NaOH}\) solution to form \(\mathrm{Y}\) and \(\mathrm{H}_{2}\). Aqueous solution of \(\mathrm{Y}\) is heated to \(323-333 \mathrm{~K}\) and on passing \(\mathrm{CO}_{2}\) into it, \(\mathrm{Na}_{2} \mathrm{CO}_{3}\) and \(\mathrm{Z}\) were formed. When \(Z\) is heated to \(1200^{\circ} \mathrm{C}, \mathrm{Al}_{2} \mathrm{O}_{3}\) is formed. \(\mathrm{X}, \mathrm{Y}\) and \(\mathrm{Z}\) respectively are (a) \(\mathrm{Al}, \mathrm{Al}(\mathrm{OH})_{3}, \mathrm{AlCl}_{3}\) (b) \(\mathrm{Al}, \mathrm{NaAlO}_{2}, \mathrm{Al}(\mathrm{OH})_{3}\) (c) \(\mathrm{Zn}, \mathrm{Na}_{2} \mathrm{ZnO}_{2}, \mathrm{Al}(\mathrm{OH})_{3}\) (d) \(\mathrm{Al}, \mathrm{AlCl}_{3}, \mathrm{NaAlO}_{2}\)
Problem 78
Destructive distillation of coal does not give: (a) Sarbides (b) Ammonia (c) Gas carbon (d) Coke
Problem 79
Which of the following is a ferrous alloy? (a) German silver (b) Gun metal (c) Nichrome (d) Devarda's alloy
