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प्रश्न
How would you explain the lower atomic radius of Ga as compared to Al?
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उत्तर
| Atomic radius (in pm) | |
| Aluminium | 143 |
| Gallium | 135 |
Although Ga has one shell more than Al, its size is lesser than Al. This is because of the poor shielding effect of the 3d-electrons. The shielding effect of d-electrons is very poor and the effective nuclear charge experienced by the valence electrons in gallium is much more than it is in the case of Al.
संबंधित प्रश्न
If B–Cl bond has a dipole moment, explain why BCl3 molecule has zero dipole moment.
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Which of the following oxides is acidic in nature?
Ionisation enthalpy (∆iH1kJ mol–1) for the elements of Group 13 follows the order.
Explain why the following compounds behave as Lewis acids?
BCl3
Explain why the following compounds behave as Lewis acids?
AlCl3
When BCl3 is treated with water, it hydrolyses and forms [B[OH]4]– only whereas AlCl3 in acidified aqueous solution forms [Al(H2O)6]3+ ion. Explain what is the hybridisation of boron and aluminium in these species?
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Pb4+ acts as an oxidising agent but Sn2+ acts as a reducing agent.
Explain the following:
Electron gain enthalpy of chlorine is more negative as compared to fluorine.
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\[\ce{X ->[Δ][370 K] HBO2 ->[Δ][> 370 K] Z}\]
Match the species given in Column I with properties given in Column II.
| Column I | Column II |
| (i) Diborane | (a) Used as a flux for soldering metals |
| (ii) Galluim | (b) Crystalline form of silica |
| (iii) Borax | (c) Banana bonds |
| (iv) Aluminosilicate | (d) Low melting, high boiling, useful for measuring high temperatures |
| (v) Quartz | (e) Used as catalyst in petrochemical industries |
Match the species given in Column I with the hybridisation given in Column II.
| Column I | Column II |
| (i) Boron in [B(OH)4]– | (a) sp2 |
| (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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Ionisation enthalpy
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Metallic character
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PbO2 is a stronger oxidising agent than SnO2
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AlCl3 , AlCl
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