Question

(a) explain the following properties of hybrids of group 16 elements H2O H2S H2Se h2te (I) boiling point (II) Thermal stability (III) Reducing power (IV) Acidic nature
(b) Name two poisonous gases which can be prepared from chlorine gas​

Answer 1

a.The properties of hybrids of group 16 elements are given below

1 .boiling point of H2O is 100°c

boiling point of H2S is -60°c

boiling point of H2Se is -41.25°c

& the boiling point of H2te is -2.2°c

2.the thermal stability which is one of important property of group 16 can be described as H20>H2S>H2Se>H2Te

3.the reducing power can be described as H20< H2S< H2Se< H2Te

4. The acidic Nature can be described as H2O <H2S< H2Se<H2Te

b. The name of the two poisonous gases which can be prepared from chlorine gas are Phosgene & Musland gas

Answer 2

Among the hydrides of Gr 16 elements,

(a) (H2O, H2S, H2Se, H2Te ) ,

I) the boiling point order is as follows :

H2O> H2Te >H2Se >H2S

The immensely high boiling point of water is due to intermolecular hydrogen bonding among its molecules.

Aming the others, the boiling point increases with increase in atomic number.

ll) The thermal stability gradually decreases as we go down the group which can be explained by decreasing bond dissosiation enthalpies.

lll) Except H20 all other hydrides show reducing property which gradually increases down the group due to decrease in bond enthalpy.

IV) Same is the case for acidic nature, the higher the reducing power or the lesser the bond dissosiation enthalpy the easier it is to release H+ ions and hence the more acidic the hydride is. Thus,

H2Te >H2Se >H2S> H2O (acidity)

(b) Two poisonous gases that can be prepared from chlorine gas are : (i) Phosgene (COCl2)

(ii) Mustard gas (C4H8Cl2S)