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Question
Identify the compounds A, X and Z in the following reactions:
\[\ce{X ->[Δ][370 K] HBO2 ->[Δ][> 370 K] Z}\]
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Solution
\[\ce{\underset{(X)}{H3BO3} ->[Δ, 370 K] \underset{Metaboric acid}{HBO2} + H2O}\]
\[\ce{4HBO2 ->[Δ, 370 K][-H2O] \underset{Tetraboric acid}{[H2B4O7]} ->[Read heat] \underset{Boric trioxide (Z)}{2B2O3} + H2O}\]
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| Column I | Column II |
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| (ii) Galluim | (b) Crystalline form of silica |
| (iii) Borax | (c) Banana bonds |
| (iv) Aluminosilicate | (d) Low melting, high boiling, useful for measuring high temperatures |
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| Column I | Column II |
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| (ii) Aluminium in [Al(H2O)6]3+ | (b) sp3 |
| (iii) Boron in B2H6 | (c) sp3d2 |
| (iv) Carbon in Buckminsterfullerene | |
| (v) Silicon in \[\ce{SiO^{4-}4}\] | |
| (vi) Germanium in [GeCl6]2– |
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