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प्रश्न
Describe the general trends in the following properties of the elements in Groups 13 and 14.
Atomic size
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उत्तर
Grp-13 The atomic size of the boron family follows the irregular trend. Generally, down the group the size increases but Gallium has a smaller atomic radius than Aluminium due to the poor shielding effect of 3d-orbitals.
Order: B < Ga < Al < In < Ti
Grp-14 The size of the carbon family is smaller than the modern family and as we move down the group the atomic size increases regularly. The increase in covalent radius from carbon to silicon is prominent while from Silicon to lead a small increase in covalent radius is observed; this is due to the presence of completely filled D and f-orbital in the heavier members.
Order: C < Si < Ge < Sn < Pb
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संबंधित प्रश्न
How can you explain higher stability of BCl3 as compared to TlCl3?
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How would you explain the lower atomic radius of Ga as compared to Al?
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Dry ice is ______.
Explain the following:
Boron does not exist as B3+ ion.
Explain the following:
PbX2 is more stable than PbX4.
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Tl (NO3)3 acts as an oxidising agent.
Identify the compounds A, X and Z in the following reactions:
\[\ce{A + 2HCl + 5H2O -> 2NaCl + X}\]
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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 |
Account for the following observations:
The +1 oxidation state of thallium is more stable than its +3 state.
Three pairs of compounds are given below. Identify that compound in each of the pairs which has group 13 element in more stable oxidation state. Give reason for your choice. State the nature of bonding also.
TlCl3, TlCl
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