Advertisements
Advertisements
प्रश्न
Ionisation enthalpy (∆iH1kJ mol–1) for the elements of Group 13 follows the order.
पर्याय
B > Al > Ga > In > Tl
B < Al < Ga < In < Tl
B < Al > Ga < In > Tl
B > Al < Ga > In < Tl
Advertisements
उत्तर
B > Al < Ga > In < Tl
Explanation:
On moving down the group from B to Tl, a regular decreasing trend in the ionisation energy values is not observed.
| Element | B | Al | Ga | In | Tl |
| I.E. (kJ/mol) | 801 | 577 | 579 | 558 | 589 |
In Ga, there are ten d-electrons in the penultimate shell which screen the nuclear charge less effectively and thus, outer electron is held firmly. As a result, the ionisation energy of both A1 and Ga is nearly the same. The increase in ionisation energy from In to Tl is due to poor screening effect of 14f electrons present in the inner shell.
APPEARS IN
संबंधित प्रश्न
How can you explain higher stability of BCl3 as compared to TlCl3?
What do you understand by inert pair effect?
Write a balanced equation for B2H6 + NH3 → ?
The geometry of a complex species can be understood from the knowledge of type of hybridisation of orbitals of central atom. The hybridisation of orbitals of central atom in [Be(OH)4]– and the geometry of the complex are respectively.
Which of the following oxides is acidic in nature?
In the structure of diborane ______.
A compound X, of boron reacts with NH3 on heating to give another compound Y which is called inorganic benzene. The compound X can be prepared by treating BF3 with Lithium aluminium hydride. The compounds X and Y are represented by the formulas.
The most commonly used reducing agent is ______.
Dry ice is ______.
Cement, the important building material is a mixture of oxides of several elements. Besides calcium, iron and sulphur, oxides of elements of which of the group (s) are present in the mixture?
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:
Boron does not exist as B3+ ion.
Explain the following:
Tl (NO3)3 acts as an oxidising agent.
Identify the compounds A, X and Z in the following reactions:
\[\ce{A + 2HCl + 5H2O -> 2NaCl + X}\]
Describe the general trends in the following properties of the elements in Groups 13 and 14.
Ionisation enthalpy
Describe the general trends in the following properties of the elements in Groups 13 and 14.
Oxidation states
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
A group 13 element ‘X’ reacts with chlorine gas to produce a compound XCl3. XCl3 is electron deficient and easily reacts with NH3 to form \[\ce{Cl3X –> NH3}\] adduct; however, XCl3 does not dimerize X is ______.
