Introduction to Alkanes.

Hydrocarbons are organic compounds containing carbon and hydrogen.

The carbon atoms in the hydrocarbons can be linked by different types of bonds.

Depending on the C-C bond in the hydrocarbon, they can be of different types.

When all the C-C bonds in the hydrocarbon are single bonds, it is part of a group called alkanes.

Alkanes are hydrocarbons with all carbon-carbon single bonds. Due to this, alkanes are saturated hydrocarbons.

All the alkanes can be found by a single general formula.

We can find different alkanes by putting in different values of n.

So the first member of alkanes is found by putting n = 1. It must contain one carbon atom.

This alkane is named as methane. because it has 1 atom and because it is an alkane.

Methane has 1 atom. has 4 valence . It shares 1 with each of the 4 atoms. So the structure of methane becomes this.

We can simplify this by just drawing the atoms and dots. This will be the electron dot structure of methane.

If we replace the shared bond with , then we will get the structural formula of methane.

Now we will find the alkane when n = 2

This alkane will have the formula

This alkane is named as ethane. because it has 2 atoms and because it is an alkane

In ethane, the two atoms share one with each other.

The remaining 3 on each C are shared with 3 atoms.

So the electron dot structure of ethane is shown here.

The structural formula of ethane is shown here.

Let's find the alkane when n = 3

This alkane will have formula

This compound is named as propane. because it has 3 atoms and because it is an alkane.

In propane, all the 3 atoms are joined by single bonds.

The first and the last have shared 1 electron. So each of the will bond with 3 to satisfy its valency. Valency of the middle is satisfied by bonding with 2 atoms.

Similarly, on increasing n, we get higher alkanes like butane, pentane, hexane, etc.

Alkanes are saturated hydrocarbons containing a single bond between all the carbon atoms.

The general formula for alkanes is shown above.

Methane, ethane, and propane are some of the examples of alkanes.

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