Chapter 10

Silicon has the characteristics of a: (a) Non metal (b) Metalloid (c) Metal (d) None of these

Graphite is a good conductor of electricity because if contains: (a) Mobile electrons (b) Bonded electrons (c) Strong \(\mathrm{C}=\mathrm{C}\) bonds (d) Strong \(\mathrm{C}-\mathrm{C}\) bonds

Borax is (a) \(\mathrm{Na}_{2}\left[\mathrm{~B}_{4} \mathrm{O}_{5}(\mathrm{OH})_{4}\right] .8 \mathrm{H}_{2} \mathrm{O}\) (b) \(\left.\mathrm{Na}_{2}\left[\mathrm{~B}_{4} \mathrm{O}_{2}(\mathrm{OH})\right)_{10}\right] \cdot 5 \mathrm{H}_{2} \mathrm{O}\) (c) \(\mathrm{Na}_{2}\left[\mathrm{~B}_{4} \mathrm{O}_{5}(\mathrm{OH})_{6}\right] .7 \mathrm{H}_{2} \mathrm{O}\) (d) \(\mathrm{Na}_{2}\left[\mathrm{~B}_{4} \mathrm{O}_{3}(\mathrm{OH})_{8}\right] \cdot 6 \mathrm{H}_{2} \mathrm{O}\)

Sodium nitroprusside when added to an alkaline solution of sulphide ions produce: (a) Purple colouration (b) Blue colouration (c) Red colouration (d) Brown colouration

Boric acid is polymeric due to (a) Its geometry (b) Its presence of hydrogen bonds (c) Its acidic nature (d) Its monobasic nature

Which one of the following allotropic forms of carbon is isomorphous with crystalline silicon? (a) Coal (b) Diamond (c) Coke (d) Graphite

Coal gas: (a) Is not a good fuel (b) Is not used for lighting purpose (c) Burns with non-smoky flame (d) Burns with a smoky flame

Which of the following compounds contain boron? (a) Colemanite (b) Cristoballite (c) Kernite (d) Both \(\mathrm{A}\) and \(\mathrm{C}\)

An ideal mixture of producer gas contains: (a) \(65 \% \mathrm{CO}, 35 \% \mathrm{~N}_{2}\) (b) \(65 \% \mathrm{CO}, 30 \% \mathrm{~N}_{2}\) and \(5 \% \mathrm{CO}_{2}\) (c) \(35 \% \mathrm{CO}, 65 \% \mathrm{~N}_{2}\) (d) \(30 \% \mathrm{CO}, 65 \% \mathrm{~N}_{2}\) and \(5 \% \mathrm{CO}_{2}\)

One can obtain a silica garden if: (a) Silicon salts are grown in garden (b) Crystals of coloured cations are added to a strong solution of sodium silicate (c) Silicon tetrafluoride is hydrolysed (d) Sodium silicate solution is heated with base