In which of the following reactions, hydrogen is liberated? (i) $\mathrm{Al}(s)+\mathrm{HCl}(a q) \longrightarrow$ (ii) $\mathrm{Al}(s)+\mathrm{NaOH}(a q) \longrightarrow$ (iii) $\mathrm{NaBH}_4+\mathrm{I}_2 \longrightarrow$

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Aicharya · Accepted Answer

(i) $2 \mathrm{Al}(s)+6 \mathrm{HCl}(a q) \longrightarrow 2 \mathrm{AlCl}_3(a q)+3 \mathrm{H}_2$ (ii) $ \begin{aligned} 2 \mathrm{Al}(s)+2 \mathrm{NaOH}(a q) \longrightarrow & \ & 2 \mathrm{Na}\left[\mathrm{Al}(\mathrm{OH})_4ight]+3 \mathrm{H}_2 \ & \begin{array}{l} 	ext { Sodium tetrahydroxo } \ 	ext { aluminate (III) } \end{array} \end{aligned} $ (iii) $ \begin{aligned} \mathrm{NaBH}_4+\mathrm{I}_2 \longrightarrow & \mathrm{BH}_3+\mathrm{NaI}+\mathrm{HI} \ & \downarrow\left(\mathrm{NaBH}_4ight) \ & 2 \mathrm{BH}_3+2 \mathrm{NaI}+\mathrm{H}_2 \end{aligned} $

In which of the following reactions, hydrogen is liberated? (i) $\mathrm{Al}(s)+\mathrm{HCl}(a q)…

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