Problem 136
Excess of \(\mathrm{Na}^{+}\) ions in human system causes: (a) Anaemia (b) High blood pressure (c) Diabetes (d) Low blood pressure
Problem 137
Crystalline sodium chloride is a bad conductor of electricity because: (a) It contains free molecules (b) The ions present in it are not free to move (c) It does not possess ions (d) It contains only molecules
Problem 138
Which one of the following reactions is not associated with the Solvay process of manufacture of sodium carbonate? (a) \(\mathrm{NaCl}+\mathrm{NH}_{4} \mathrm{HCO}_{3} \rightarrow \mathrm{NaHCO}_{3}+\mathrm{NH}_{4} \mathrm{Cl}\) (b) \(2 \mathrm{NaOH}+\mathrm{CO}_{2} \rightarrow \mathrm{Na}_{2} \mathrm{CO}_{3}+\mathrm{H}_{2} \mathrm{O}\) (c) \(2 \mathrm{NaHCO}_{3} \rightarrow \mathrm{Na}_{2} \mathrm{CO}_{3}+\mathrm{H}_{2} \mathrm{O}+\mathrm{CO}_{2}\) (d) \(\mathrm{NH}_{3}+\mathrm{H}_{2} \mathrm{CO}_{3} \rightarrow \mathrm{NH}_{4} \mathrm{HCO}_{3}\)
Problem 139
\(\mathrm{KO}_{2}\) (potassium super oxide) is used in oxygen cylinders in space and submarines because it: (a) Produces ozone (b) Absorbs \(\mathrm{CO}_{2}\) (c) Absorbs \(\mathrm{CO}_{2}\) and increase \(\mathrm{O}_{2}\) contents (d) Eliminates moisture
Problem 140
A metal \(\mathrm{M}\) readily forms water soluble sulphate \(\mathrm{MSO}_{4}\), water insoluble hydroxide \(\mathrm{M}(\mathrm{OH})_{2}\) and oxide MO which becomes inert on heating. The hydroxide is soluble in \(\mathrm{NaOH}\). The \(\mathrm{M}\) is: (a) \(\mathrm{Mg}\) (b) \(\mathrm{Sr}\) (c) \(\mathrm{Be}\) (d) \(\mathrm{Ca}\)
Problem 141
The metallic sodium dissolves in liquid ammonia to form a deep blue coloured solution. The deep blue colour is due to formation of: (a) Solvated electron, e \(\left(\mathrm{NH}_{3}\right) \mathrm{x}^{-}\) (b) Solvated atomic sodium, \(\mathrm{Na}\left(\mathrm{NH}_{3}\right) \mathrm{y}\) (c) \(\left[\mathrm{Na}^{+}+\mathrm{Na}^{-}\right]\) (d) \(\mathrm{NaNH}_{2}+\mathrm{H}_{2}\)
Problem 142
Identify the correct order of acidic strengths of \(\mathrm{CO}_{2}\), \(\mathrm{CuO}, \mathrm{CaO}, \mathrm{H}_{2} \mathrm{O}\) (a) \(\mathrm{CaO}<\mathrm{H}_{2} \mathrm{O}<\mathrm{CuO}<\mathrm{CO}_{2}\) (b) \(\mathrm{H}_{2} \mathrm{O}<\mathrm{CO}_{2}<\mathrm{CaO}<\mathrm{CuO}\) (c) \(\mathrm{H}_{2} \mathrm{O}<\mathrm{CuO}<\mathrm{CaO}<\mathrm{CO}_{2}\) (d) \(\mathrm{CaO}<\mathrm{CuO}<\mathrm{H}_{2} \mathrm{O}<\mathrm{CO}_{2}\)
Problem 143
Carnallite on electrolysis gives: (a) \(\mathrm{Na}\) and \(\mathrm{CO}_{2}\) (b) \(\mathrm{Mg}\) and \(\mathrm{Cl}_{2}\) (c) \(\mathrm{Al}\) and \(\mathrm{Cl}_{2}\) (d) \(\mathrm{Ca}\) and \(\mathrm{Cl}_{2}\)
Problem 146
On dissolving moderate amount of sodium metal in liquid \(\mathrm{NH}_{3}\) at low temperature, which one of the following does not occur? (a) \(\mathrm{Na}^{+}\) ions are formed in the solution. (b) Liquid \(\mathrm{NH}_{3}\) solution remains diamagnetic. (c) Liquid \(\mathrm{NH}_{3}\) solution becomes good conductor of electricity. (d) Blue coloured solution is obtained.
Problem 147
Beryllium and aluminium exhibit many properties which are similar. But the two elements differ in: (a) Forming polymeric hydrides (b) Forming covalent halides (c) Exhibiting maximum covalency in compounds (d) Exhibiting amphoteric nature in their oxides.
