Problem 11
The pair of compounds which cannot exist together is: (a) \(\mathrm{NaHCO}_{3} \& \mathrm{NaOH}\) (b) \(\mathrm{Na}_{2} \mathrm{CO}_{3} \& \mathrm{NaHCO}_{3}\) (c) \(\mathrm{Na}_{2} \mathrm{CO}_{3} \& \mathrm{NaOH}\) (d) \(\mathrm{NaHCO}_{3} \& \mathrm{NaCl}\)
Problem 12
Which one of the following compounds in aqueous solution gives a white precipitate with perchloric acid? (a) \(\mathrm{NaCl}\) (b) \(\mathrm{MgCl}_{2}\) (c) \(\mathrm{KCl}\) (d) \(\mathrm{FeCl}_{3}\)
Problem 13
As the alkaline earth metals (except Be) tend to lose their valence electrons readily, they act as: (a) Bases (b) Strong reducing agents (c) Weak oxidizing agents (d) Weak reducing agents
Problem 14
In view of their low ionization energies, the alkali metals are: (a) Strong oxidizing agents (b) Weak oxidizing agents (c) Strong reducing agents (d) Weak reducing agents
Problem 15
When sodium is treated with sufficient oxygen/air, the product obtained is: (a) \(\mathrm{NaO}_{2}\) (b) \(\mathrm{NaO}\) (c) \(\mathrm{Na}_{2} \mathrm{O}\) (d) \(\mathrm{Na}_{2} \mathrm{O}_{2}\)
Problem 16
Which of the following has lowest melting point? (a) \(\mathrm{Cs}\) (b) \(\mathrm{Na}\) (c) Li (d) \(\mathrm{K}\)
Problem 17
The ionic mobility of alkali metal ions in aqueous solution is maximum for: (a) \(\mathrm{K}^{+}\) (b) \(\mathrm{Rb}^{+}\) (c) \(\mathrm{Li}^{+}\) (d) \(\mathrm{Na}^{+}\)
Problem 18
As the nuclear charge increases from neon to calcium, the orbital energies: (a) Increase very slow (b) Increase very rapidly (c) Fall (d) Increase
Problem 19
Which of the following has maximum ionization energy? (a) \(\mathrm{Ca} \rightarrow \mathrm{Ca}^{2+}+2 \mathrm{e}^{-}\) (b) \(\mathrm{Mg} \rightarrow \mathrm{Mg}^{2+}+2 \mathrm{e}^{-}\) (c) \(\mathrm{Ba} \rightarrow \mathrm{Ba}^{+}+\mathrm{e}^{-}\) (d) \(\mathrm{Be} \rightarrow \mathrm{Be}^{+}+\mathrm{e}^{-}\)
Problem 21
\(\mathrm{Mg}\) is an important component of which biomolecule occurring extensively in living world? (a) Chlorophyll (b) Haemoglobin (c) ATP (d) Florigen
