Advertisements
Advertisements
प्रश्न
Explain why is there a phenomenal decrease in ionisation enthalpy from carbon to silicon?
Advertisements
उत्तर
Ionisation enthalpy of carbon (the first element of group 14) is very high (1086 kJ/mol). This is expected owing to its small size. However, on moving down the group to silicon, there is a sharp decrease in the enthalpy (786 kJ). This is because of an appreciable increase in the atomic sizes of elements on moving down the group.
संबंधित प्रश्न
Discuss the pattern of variation in the oxidation states of C to Pb.
Rationalise the given statement and give a chemical reaction:
Lead (II) chloride reacts with Cl2 to give PbCl4.
Write suitable chemical equations to show the nature of the following oxide.
Tl2O3
Elements of group 14 ________.
Rationalise the given statement and give a chemical reaction:
Lead is known not to form an iodide, PbI4.
Classify the following oxide as neutral, acidic, basic or amphoteric:
CO2
The linear shape of CO2 is due to:
(i) sp3 hybridisation of carbon.
(ii) sp hybridisation of carbon.
(iii) pπ – pπ bonding between carbon and oxygen.
(iv) sp2 hybridisation of carbon.
Give reasons for the following:
CCl4 is immiscible in water, whereas SiCl4 is easily hydrolysed.
Explain the following:
Silicon forms \[\ce{SiF^{2-}6}\] ion whereas corresponding fluoro compound of carbon is not known.
Explain the following:
CO2 is a gas whereas SiO2 is a solid.
The +1 oxidation state in group 13 and +2 oxidation state in group 14 becomes more and more stable with increasing atomic number. Explain.
Carbon and silicon both belong to the group 14, but inspite of the stoichiometric similarity, the dioxides, (i.e., carbon dioxide and silicon dioxide), differ in their structures. Comment.
Explain the following:
Carbon shows catenation property but lead does not.
A tetravalent element forms monoxide and dioxide with oxygen. When air is passed over heated element (1273 K), producer gas is obtained. Monoxide of the element is a powerful reducing agent and reduces ferric oxide to iron. Identify the element and write formulas of its monoxide and dioxide. Write chemical equations for the formation of producer gas and reduction of ferric oxide with the monoxide.
Which one of the following compounds of Group–14 elements is not known?
