What is the general formula for alkanes?

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The general formula for alkanes is CnH2n + 2, where 'n' represents the number of carbon atoms in the molecule. Alkanes are a class of hydrocarbons that are saturated, meaning they contain only single bonds between carbon atoms. This saturation allows each carbon atom to bond with hydrogen atoms to maximize its four valence electrons, resulting in the addition of two hydrogen atoms for each carbon atom plus two extra hydrogens for the terminal carbons.

For example, if you have one carbon atom (n=1), the formula yields C1H(2*1 + 2) = CH4, which is methane, the simplest alkane. As you increase the number of carbon atoms, you can see how the molecule continues to adhere to the formula, thereby maintaining its characteristics as an alkane. The +2 in the formula signifies that there are two additional hydrogen atoms compared to the number derived from simply doubling the carbon count. This specific structural characteristic is critical in distinguishing alkanes from other types of hydrocarbons, such as alkenes and alkynes, which have different bonding structures and, consequently, different formulas.

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