NEET Practice Questions (MCQs) with Answers & Solutions

Liquid hydrogen delivers a specific impulse about 30%-40% higher than most other rocket fuels. Liquid oxygen and liquid hydrogen are used as the propellant in the high efficiency main engines of the Space Shuttle.

oxidation no oxygen goes from -1 to zero 

(b) Alkali metal hydroxides are highly soluble in water.

(c)

 $$\begin{gathered} {\mathrm{AlCl}}_3 + 3\mathrm{NaOH} \stackrel{ }{\to } \mathrm{Al}(\mathrm{OH}{)}_3 + 3\mathrm{NaCl} \\ \mathrm{Al}(\mathrm{OH}{)}_3 + 3\mathrm{NaOH} \stackrel{ }{\to } {\mathrm{Na}}_3{\mathrm{AlO}}_3 + 3{\mathrm{H}}_2\mathrm{O} \\ \mathrm{soluble} \end{gathered}$$

(c) Violet colour to flame is characteristic of potassium. Also aqueous solution of K₂CO₃ is alkaline.

(a) Alkali metals are strongest reducing agents. Also, their reducing power increases down the group.

(c) NaOH absorbs moisture and CO₂ from air to form Na₂CO₃, 

$2\mathrm{NaOH} + {\mathrm{CO}}_2 \underset{ }{\to } {\mathrm{Na}}_2{\mathrm{CO}}_3 + {\mathrm{H}}_2\mathrm{O}$2

(C) $\mathrm{KI} + {\mathrm{I}}_2 \stackrel{ }{\to }{\mathrm{KI}}_3$

(d) ${\mathrm{CsBr}}_3 \stackrel{ }{\to } {\mathrm{Cs}}^{+}+ {\mathrm{Br}}_3^{-}$

(d) It is chemical formula of Hypo.