मराठी
कर्नाटक बोर्ड पी.यू.सी.पीयूसी विज्ञान 2nd PUC Class 12

The HNH angle value is higher than HPH, HAsH and HSbH angles. Why?

Advertisements
Advertisements

प्रश्न

The HNH angle value is higher than HPH, HAsH and HSbH angles. Why? [Hint: Can be explained on the basis of sp3 hybridisation in NH3 and only s−p bonding between hydrogen and other elements of the group].

Advertisements

उत्तर १

Hydride NH3 PH3 AsH3 SbH3

H−M−H angle 107° 92° 91° 90°

The above trend in the H−M−H bond angle can be explained on the basis of the electronegativity of the central atom. Since nitrogen is highly electronegative, there is high electron density around nitrogen. This causes greater repulsion between the electron pairs around nitrogen, resulting in maximum bond angle. We know that electronegativity decreases on moving down a group. Consequently, the repulsive interactions between the electron pairs decrease, thereby decreasing the H−M−H bond angle.

shaalaa.com

उत्तर २

In all these cases, the central atom is sp3 hybridized. Three of the four sp3 orbitals form three σ-bonds, while the fourth contains the lone pair of electrons. On moving down from N to Sb, the electronegativity of the central atom goes on decreasing. As a result of this, bond  pairs of electrons lie away and away from the central atom. This is because of the force of repulsion between the adjacent bond pairs goes on decreasing and the bond angles keep on decreasing from NH3to SbH3. Thus, bond angles are in the order:

HNH    >    HPH   > HasH    >  HSbH

(107.8º)       (93.6º)   (91.8º)       (91.3º)

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?

संबंधित प्रश्‍न

Account for the following: Oxygen shows catenation behavior less than sulphur.


a. Explain the trends in the following properties with reference to group 16:

1 Atomic radii and ionic radii

2 Density

3 ionisation enthalpy

4 Electronegativity

b. In the electolysis of AgNO3 solution 0.7g of Ag is deposited after a certain period of time. Calulate the quantity of electricity required in coulomb. (Molar mass of Ag is 107.9g mol-1)

 


Account for the following : There is large difference between the melting and boiling points of oxygen and sulphur.


Give reasons for the following : H2Te is the strongest reducing agent amongst all the hydrides of Group 16 elements.


Give reasons for the following : Oxygen has less electron gain enthalpy with negative sign than sulphur.


Knowing the electron gain enthalpy values for \[\ce{O -> O-}\] and \[\ce{O -> O^{2-}}\] as −141 and 702 kJ mol−1 respectively, how can you account for the formation of a large number of oxides having O2− species and not O?

(Hint: Consider lattice energy factor in the formation of compounds).


Explain why inspite of nearly the same electronegativity, oxygen forms hydrogen bonding while chlorine does not.


Arrange the following in the order of property indicated for the given set:

F2, Cl2, Br2, I2 - increasing bond dissociation enthalpy.


Draw the structures of `H_3PO_2`

 


Arrange the following in the order of the property indicated against set :
H2O, H2S, H2Se, H2Te − increasing acidic character.


 Give reactions for the following: 
O – O single bond is weaker than S – S single bond. 


Give a reason for the following:

Fluorine gives only one oxide but chlorine gives a series of oxides.


The formation of \[\ce{O^+_2[PtF6]^-}\] is the basis for the formation of first xenon compound. This is because ____________.


Strong reducing behaviour of \[\ce{H3PO2}\] is due to ______.


Out of \[\ce{H2O}\] and \[\ce{H2S}\], which one has higher bond angle and why?


The correct order of ΔiHs among the following elements is


What is the basicity of \[\ce{H3PO4}\]?


Given below are two statements:

Statement I: The boiling point of hydrides of Group 16 elements follows the order:

H2O > H2Te > H2Se > H2S

Statement II: On the basis of molecular mass, H2O is expected to have a lower boiling point than the other members of the group but due to the presence of extensive H-bonding in H2O, it has a higher boiling point.

In the light of the above statements, choose the correct answer from the options given below:


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×