All the carbon family member are solids. Carbon and silicon are non metals, germanium is metalloid, whereas tin and lead are soft metals with low melting points. The M.P. and B.P. of carbon family are higher than those of corresponding elements of boron family.
Oxidation of carbon family
The carbon family elements have four electrons in outer most shell. All the elements show an oxidation state of +4. However, as we move down the group from C to Pb, the stability of +4 oxidation state decreases while that of +2 oxidation state increases due to inert pair effect.
Trend in oxidising and reducing properties of carbon family
1. Sn in +2 oxidation state is reducing agent. 2. Lead compounds are stable in +2 state. Lead in +4 oxidation state acts as oxidizing agent, so the oxidizing and reducing nature from top to bottom become specific. 3. Carbon always present in +2 to +4 oxidation states.
Tendency of formation of p(pi) - p(pi) bonds in carbon family
1. In carbon family Carbon have tendency to form pπ−pπ multiple bonds with itself and with other atoms of small size and high electronegativity, because its size is small, but other element with heavier nucleus do not form this type of bond due to large and diffused atomic orbitals.
Tendency to form d(pi) - p(pi) bonds in carbon family
1. Carbon does not have d-orbitals and hence it does not form dπ−pπ bonds. 2. However, silicon and other heavier elements of this group because of presence of vacant d-orbitals in them tend to form dπ−pπ bond.
Reactivity of carbon towards oxygen and their properties
All the element of group 14 when heated in oxygen form oxides. These are mainly of two types, i.e., monoxides of the formula MO and dioxides of the formula MO2. These oxides shows the properties like acid-base character, reducing-oxidizing nature etc.
Reactivity of carbon family towards water and their properties
Carbon, silicon and germanium do not decomposes water at all. Tin decomposes steam to form tin oxide and dihydrogen gas.
Reactivity of carbon family towards halogens and their properties
Except C all member of carbon series forms halides of formula MX4, which are covalent in nature.
Maximum covalency and tendency to form complexes in carbon family
Carbon because of the absence of d-orbitals, cannot expand its valency and hence, its maximum covalency or coordination number is four. But other member show coordination greater than 4 forming penta-coordinated and hexa-coordinated complexes.