Physical Properties of Group-14 Elements

Group 14 elements also called as Carbon group. The members of this group are:
• Carbon
• Silicon
Germanium
• Tin
• Lead
These elements are widely found on Earth like silicon is the second most abundant element in the earth’s crust and carbon is the seventeen most abundant as per mass. Germanium is very rare in nature. These compounds play a major role in our daily life in multiple ways.For example, Carbon dioxide is very important for photosynthesis which in turn is responsible for the life on earth. Silicon plays a massive role in the development of technology. The trends in the physical properties down the group are mention below:

These elements are widely found on Earth like silicon is the second most abundant element in the earth’s crust and carbon is the seventeen most abundant as per mass. Germanium is very rare in nature. These compounds play a major role in our daily life in multiple ways.For example, Carbon dioxide is very important for photosynthesis which in turn is responsible for the life on earth. Silicon plays a massive role in the development of technology. The trends in the physical properties down the group are mention below:
Covalent radius: Down the group, the covalent radius increases. The size difference between silicon and germanium is small. This is because germanium consists of a complete 3d orbital which is responsible for failing to shield the nuclear charge. A small size difference is observed between Sn and Pb for the same reason as mention above due to completely filled 4f shells.

Ionization energy: It is the energy required to remove the loosely bound electrons. The ionization energy decreases down the group in an irregular way due to the filling of d and f shells.

Melting point: The melting point of carbon is extremely high. All the elements of group-14 possess diamond-type lattice structure which is highly stable in nature. The process of melting results in the breakage of these highly stable lattice structures. Hence, a large energy is required for the breakage. Down the group, the melting point decreases as the M-M bonds are reduced as the size of the atoms increases. Tin and lead are metals. Hence the melting points of these elements are much lower.

Metallic and non-metallic character: As we go down the group the atomic number increases and it changes from nonmetals to metals. Carbon and silicon exhibit the characteristics of non-metals. Germanium possesses intermediate characteristics of metals and non-metals i.e. metalloids and tin and lead are metals. The appearances and structures prove the metallic characteristics of these elements.

Four-covalent compounds: Four covalent compounds are compounds in which the four electrons in the valence shell play an active role in bonding. Most of the group 14 element possesses this property.

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Continuing the inheritance story from the where we left – now the ore is concentrated. What would you do next with the now concentrated and dried ore?