--%>
Assignment Help - homework help

Explanation of oxygen family.

Group 16 of periodic table contains five elements namely, oxygen (O), sulphur (S), selenium (Se), tellurium (Te) and polonium (Po). These are collectively known as chalcogens or ore forming elements because many metal ores occur as oxides and sulphides. These elements belong to p-block. The first four members of group 16 are non-metals. Polonium has metallic character and is a radioactive element with a very short period.

Oxygen, the most abundant element, is a vital element of atmosphere and ocean. It composes 46.6% of earth's crust. It forms about 21% of air as the free element and 89% of the ocean by weight. Sulphur is less abundant and occurs about 0.052% of the earth's crust. Sulphur is also referred as Brim stone. The name sulphur is derived from Sanskrit word 'Sulveri' which means 'killer of copper'. Compared to oxygen and sulphur the other members of this group are rare.

Atoms of these elements have outer electronic configuration as ns2np4, where n varies from 2 to 6. The electronic configurations of the elements of group 16 are shown in the table below:

Elements

At. No.

Electronic configuration

Abundance in earth's crust (ppm)

Oxygen (O)

8

[He] 2s2 2p4

4.66 × 105

Sulphur (S)

16

[Ne] 3s2 3p4

5.20 × 102

Selenium (Se)

34

[Ar] 3d10 4s2 4p4

9.0 × 10-2

Tellurium (Te)

52

[Kr] 4d10 5s2 5p4

2 × 10-3

Polonium (Po)

84

[Xe] 4f14 5d10 6s2 6p4

-


The four p-electrons of the outermost shell are arranged as px2 py1 pz1. Thus, there are two half-filled p-orbitals which are used for bonding with other elements. From the similar outer electronic configuration of these elements, it is expected that they will show similar physical and chemical properties.

Oxygen the first member of this group has very high ionization energy (1314 kJ mol-1) and differs markedly from other members of the family.

Oxygen, on the other hand, is found to exhibit remarkable resemblance with its neighbours, nitrogen and fluorine. For example, it forms strong pπ-pπ bond like nitrogen. Also it forms hydrogen bonds like nitrogen and fluorine.

   Related Questions in Chemistry

  • Q : Explain the process of adsorption of

    The extent of adsorption of a gas on a solid adsorbent is affected by the following factors: 1. Nature of the gas Since physical adsorption is non-specific in nature, every gas will get adsorbed on the

    		•
  • Q : Modern periodic table and Mendeleevs

    Differentiate between the modern periodic table and Mendeleevs table?

    		•
  • Q : Strength of dilute acid of Sulfuric acid

    Select the right answer of the question.10ml of conc.H2SO4 (18 molar) is diluted to 1 litre. The approximate strength of dilute acid could be: (a)0.18 N (b)0.09 N (c) 0.36 N (d)1800 N

    		•
  • Q : What type of bond does HCl encompass

    What type of bond does HCl encompass? Describe briefly?

    		•
  • Q : Molecular weight of solute Select right

    Select right answer of the question. A dry air is passed through the solution, containing the 10 gm of solute and 90 gm of water and then it pass through pure water. There is the depression in weight of solution wt by 2.5 gm and in weight of pure solvent by 0.05 gm. C

    		•
  • Q : What is depression in freezing point?

    Freezing point of a substance is the temperature at which solid and liquid phases of the substance coexist. It is defined as the temperature at which its solid and liquid phases have the same vapour pressure. The freezing point o

    		•
  • Q : Molarity of cane sugar solution 171 g

    171 g of cane sugar (C12H22O11)  is dissolved in one litre of water. Find the molarity of the solution: (i) 2.0 M (ii) 1.0 M (iii) 0.5 M (iv) 0.25 M Choose the right answer from above.

    		•
  • Q : Explain the polymers and its types.

    Polymers are the chief products of modern chemical industry which form the backbone of present society. Daily life without the discovery and varied applications of polymers would not have been easier and colourful. The materials made of polymers find multifarious uses and applications in all walk

    		•
  • Q : Problem on making solutions The weight

    The weight of pure NaOH needed to made 250cm3 of 0.1 N solution is: (a) 4g  (b) 1g  (c) 2g  (d) 10g Choose the right answer from above.

    		•
  • Q : P block bif3 is ionic while other

    bif3 is ionic while other trihalides are covalent in nature

    		•