--%>
Assignment Help - homework help

Explain group 15 elements.

The various elements of this group differ from one another in their chemical reactivity. Nitrogen differs from the rest of the members of the group due to its smaller size, high electronegativity, high ionization enthalpy and non-availability of d-orbitals. Nitrogen is chemically comparatively less reactive. It is because of high stability of its molecule, N2 in which the two nitrogen atoms are linked by triple bond (N ≡ N) and thus, possess high bond strength (941.4 kJ mol-1).


Among the elements of this group only nitrogen has a unique ability to form p π-p π multiple bonds with itself as well as with carbon oxygen. The multiple bonding in nitrogen occurs due to its small size. Nitrogen, thus, forms a diatomic molecule, N2. On the other hand, phosphorus, arsenic and antimony form tetrahedral molecules in their elemental state with formula E4. Each P atom is linked to three other atoms with P - P - P bond angle equal to 60°. Though phosphorus and heavier members of the family do not form p π-p πmultiple bonds easily, yet the multiple bonding of the type d π-p π can readily occur in these elements. This type of bonding is prominent for the phosphorus as is reflected in the formation of compounds such as POX3, RN = PX2, R3P = O or R3P = CH2 (R = alkylgroup).

Phosphorus and arsenic can form d π-p π bond also with transition metals their compounds like P(C2H3) and As(C6H5)3 an actas ligands. Recently, a few compounds of phosphorus and arsenic having multiple bonding like P = C, P ≡ C, P = N, P = P and As = Asgroups have been synthesized.

The common chemical characteristics of group 15 elements are discussed below:

Reactivity for hydrogen: the elements of group 15 form hydrides having the general formula EH3. All these are covalent in nature. These hydrides are listed below:

66_Group 15.png 

Reactivity towards halogen

All the elements of group 15 form two series of halides, i.e. trihalides and pentahalides of the type EX3 and EX5.

Nitrogen does not form pentahalides because of non-availability of the d-orbitals in its valence shell. Penta-halides are more covalent than trihalides. All these trihalides of these elements except those of nitrogen are stable. In case of nitrogen simply NF3 is known to be stable. The trihalides except BiF3 are predominantly covalent in character.

   Related Questions in Chemistry

  • Q : Symmetry Elements The symmetry of the

    The symmetry of the molecules can be described in terms of electrons of symmetry and the corresponding symmetry operations.Clearly some molecules, like H2O and CH4, are symmetric. Now w

    		•
  • Q : Chemists have not created a periodic

    Explain the reason behind that the chemists have not created a periodic table of compounds?

    		•
  • Q : Explain group 15 elements. The various

    The various elements

    		•
  • Q : Finding strength of HCL solution Can

    Can someone please help me in getting through this problem. 1.0 gm of pure calcium carbonate was found to require 50 ml of dilute  HCL for complete reaction. The strength of the HCL  solution is given by: (a) 4 N  (b) 2 N  (c) 0.4 N  (d) 0.2 N

    		•
  • Q : Question on molality Provide solution

    Provide solution of this question. Which of the following concentration factor is affected by change in temperature : (a)Molarity (b) Molality (c)Mole fraction (d)Weight fraction

    		•
  • Q : Mole fraction in vapours Choose the

    Choose the right answer from following. If two substances A and B have P0A P0B= 1:2 and have mole fraction in solution 1 : 2 then mole fraction of A in vapours: (a) 0.33 (b) 0.25 (c) 0.52 (d) 0.2

    		•
  • Q : Quastion of finding vapour pressure

    Vapour pressure of CCl425Degree C at is 143mm of Hg0.5gm of a non-volatile solute (mol. wt. = 65) is dissolved in 100ml CCl4 .Find the vapour pressure of the solution (Density of CCl4 = = 1.58g /cm2): (a)141.43mm (b)

    		•
  • Q : Simulate the column in HYSYS The

    The objective of this work is to separate a binary mixture and to cool down the bottom product for storage. (Check table below to see which mixture you are asked to study). 100 kmol of feed containing 10 mol percent of the lighter component enters a continuous distillation column at the m

    		•
  • Q : What is cannizaro reaction? Explain

    Aldehydes which do not have  -hydrogen atom, such as formaldehyte and benzaldehyte, when heated with concentrated (50%)alkali solutio

    		•
  • Q : Explain the process of adsorption in

    The process of adsorption can occurs in solutions also. This implies that the solid surfaces can also adsorb solutes from solutions. Some clarifying examples are listed below: (i) When an aqueous solution of ethano

    		•