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Alkanes are a class of hydrocarbons composed entirely of carbon (C) and hydrogen (H) atoms. They are known as saturated hydrocarbons because each carbon atom forms single bonds with four other atoms, typically hydrogen or another carbon. This saturation with hydrogen atoms means alkanes have reached a maximum level of hydrogen attachment possible for their carbon backbone.
Alkanes are straight or branched chain molecules and are known for their relative stability. This stability is because the carbon-carbon and carbon-hydrogen bonds are fairly strong and thus, alkanes do not react easily under normal conditions. They are generally nonpolar, which affects how they interact with other substances, particularly in terms of solubility and reactions. Common examples include methane ( CH_4 ), ethane ( C_2H_6 ), and propane ( C_3H_8 ).

• These molecules are often found in natural gas and petroleum.
• Alkanes are used widely as fuels and lubricants.
• They also serve as a foundational concept for understanding organic chemistry.

The structure of alkanes revolves around carbon atoms forming the backbone of the molecule. Carbon is a unique element because it can form four covalent bonds with other atoms, allowing for a vast array of molecular structures including chains, rings, and complex branches.
The carbon atoms in alkanes are bonded in a chain which can be either straight or branched. This arrangement contributes to how alkanes are categorized and named.

• Each additional carbon atom in an alkane increases the size and mass of the molecule.
• Carbon's valency of four means it can create stable, single-bond linkages with other carbons or hydrogens.
• This allows for the creation of vast, complex networks of bonds that define organic chemistry.

In the current exercise, understanding the role and count of carbon atoms helps in applying the alkane general formula correctly to determine the molecular formula.

The general formula for alkanes is a simple yet powerful tool for understanding the molecular composition of these hydrocarbons. Expressed as C_nH_{2n+2} , this formula provides a method for predicting the number of hydrogen atoms in an alkane based on the number of carbon atoms.
Here's how it works:

• The "n" in the formula represents the number of carbon atoms.
• The formula calculates hydrogen atoms as twice the number of carbons plus two, encapsulated in the term "2n + 2".

When applied to an exercise, such as finding the molecular formula of an alkane with 14 carbon atoms, the formula guides us to substitute "n" with 14. This results in the calculation 2*14 + 2 = 30 hydrogen atoms, yielding a molecular formula of C_{14}H_{30} .
This straightforward approach highlights the direct relationship between carbon and hydrogen atoms in alkanes, emphasizing the concept of saturation, which is inherent in their naming and properties.