This property is prominent among carbon atoms, significant among sulphur and silicon atoms and slightly present among germanium, nitrogen, selenium and tellurium atoms. The ability of greater extent of catenation of carbon atoms over silicon atoms is mainly based on the strength of carbon-carbon bonds which is much stronger than silicon — silicon bonds and also because of its small size. In addition, carbon atoms may be linked by single, double or triple bonds.
Carbon compounds, in which carbon atoms are linked by single bonds only, are called saturated compounds. Carbon compounds having double or triple or both bonds between their carbon atoms are known as unsaturated compounds. Therefore, it makes 4 bonds with other carbon atoms or monovalent atoms, to achieve noble gas configuration Neon-2,8 and becomes stable. The four valencies of carbon can be shown as —. The bonds that carbon forms with other elements are very strong which makes these compounds exceptionally stable.
The reason for the formation of strong bonds by carbon is its small size that enables the nucleus to hold on to the shared pairs of electrons strongly. The bonds formed by elements having larger atoms are much weaker.
The different structures form from the compound are called isomers. Here, prefix 'nona' means nine, therefore, this saturated hydrocarbon having seven carbon atoms is known as Nonane. Here, prefix 'deca' means ten, therefore, this saturated hydrocarbon having seven carbon atoms is known as Decane. Hydrocarbons with double or triple bonds are called Unsaturated Hydrocarbons or Unsaturated Carbon compounds.
Unsaturated Hydrocarbons can be further divided into two types: Hydrocarbons with double bonds and Hydrocarbons with triple bonds. MCQs Test. Back to 10th-science-home. Carbon and Its Compounds - Class 10th Science. Tetravalency of Carbon Carbon has four electrons in its outermost orbit. Hydrocarbons are of two types: Saturated hydrocarbons and Unsaturated hydrocarbons.
Saturated hydrocarbons are known as Alkanes. Thus, this compound is named as Butane. In the name of this caompound, 'Buta' means four and 'ane' exists for alkane. Hexane Here, prefix 'hexa' means six, therefore, this saturated hydrocarbon having six carbon atoms is known as Hexane. Two factors noticed in the case of carbon are —. Carbon has the unique ability to form bonds with other atoms of carbon, giving rise to large molecules. This property is called catenation. These compounds may have long chains of carbon, branched chains of carbon, or even carbon atoms arranged in rings.
In addition, carbon atoms may be linked by single, double, or triple bonds. Compounds of carbon, which are linked by only single bonds between the carbon atoms are called saturated compounds. Compounds of carbon having double or triple bonds between their carbon atoms are called unsaturated compounds.
No other element exhibits the property of catenation to the extent seen in carbon compounds. Silicon forms compounds with hydrogen which have chains of upto seven or eight atoms, but these compounds are very reactive.
The carbon-carbon bond is very strong and hence stable. This gives us a large number of compounds with many carbon atoms linked to each other. Since carbon has a valency of four, it is capable of bonding with four other atoms of carbon or atoms of some other mono-valent element.
Compounds of carbon are formed with oxygen, hydrogen, nitrogen, sulphur, chlorine, and many other elements giving rise to compounds with specific properties that depend on the elements other than carbon present in the molecule.
Again the bonds that carbon forms with most other elements are very strong making these compounds exceptionally stable. One reason for the formation of strong bonds by carbon is its small size.
This enables the nucleus to hold on to the shared pairs of electrons strongly. The bonds formed by elements having bigger atoms are much weaker. More to know. Organic compounds. The two characteristic features are seen in carbon, that is, tetravalency and catenation, put together give rise to a large number of compounds.
Many have the same non-carbon atom or group of atoms attached to different carbon chains. These compounds were initially extracted from natural substances and it was thought that these carbon compounds or organic compounds could only be formed within a living system.
But carbon compounds, except for carbides, oxides of carbon, carbonate, and hydrogencarbonate salts continue to be studied under organic chemistry. Saturated and Unsaturated Carbon Compounds. We have already seen the structure of methane. Another compound formed between carbon and hydrogen is ethane with a formula of C 2 H 6.
In order to arrive at the structure of simple carbon compounds, the first step is to link the carbon atoms together with a single bond Fig. For example, the structure of ethane is arrived in the following steps —. Step Figure 4. Three valencies of each carbon atom remain unsatisfied, so each is bonded to three hydrogen atoms giving :. The electron dot structure of ethane is shown in Fig.
Can you draw the structure of propane, which has the molecular formula C 3 H 8 in a similar manner? You will see that the valencies of all the atoms are satisfied by single bonds between them. Such carbon compounds are called saturated compounds. These compounds are.
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