Advertisements
Advertisements
प्रश्न
How would you explain the lower atomic radius of Ga as compared to Al?
Advertisements
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
How can you explain higher stability of BCl3 as compared to TlCl3?
Aluminium trifluoride is insoluble in anhydrous HF but dissolves on the addition of NaF. Aluminium trifluoride precipitates out of the resulting solution when gaseous BF3 is bubbled through. Give reasons.
What happens when BF3 is reacted with ammonia?
Which of the following oxides is acidic in nature?
Ionisation enthalpy (∆iH1kJ mol–1) for the elements of Group 13 follows the order.
In the structure of diborane ______.
Dry ice is ______.
Aluminium dissolves in mineral acids and aqueous alkalies and thus shows amphoteric character. A piece of aluminium foil is treated with dilute hydrochloric acid or dilute sodium hydroxide solution in a test tube and on bringing a burning matchstick near the mouth of the test tube, a pop sound indicates the evolution of hydrogen gas. The same activity when performed with concentrated nitric acid, reaction doesn’t proceed. Explain the reason.
Explain the following:
Pb4+ acts as an oxidising agent but Sn2+ acts as a reducing agent.
Complete the following chemical equations:
\[\ce{Z + 3 LiAlH4 -> X + 3LiF + 3AlF_3}\]
\[\ce{X + 6H2 -> Y + 6H2}\]
\[\ce{3X + 3O2 ->[Δ] B2O3 + 3H2O}\]
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 |
Describe the general trends in the following properties of the elements in Groups 13 and 14.
Metallic character
Describe the general trends in the following properties of the elements in Groups 13 and 14.
Oxidation states
Describe the general trends in the following properties of the elements in Groups 13 and 14.
Nature of halides
Account for the following observations:
Though fluorine is more electronegative than chlorine yet BF3 is a weaker Lewis acid than BCl3
Account for the following observations:
PbO2 is a stronger oxidising agent than SnO2
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.
AlCl3 , AlCl
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.
InCl3, InCl
Boron compounds behave as Lewis acids because of their ______.
Taking stability as the factor, which one of the following represents the correct relationship?
