(b) Pentane is the alkane with a chain of five carbon atoms. Determine its molecular formula.

Verified step by step guidance

1. Identify the general formula for alkanes, which is C_nH_{2n+2}.
2. Recognize that pentane has a chain of five carbon atoms, so n = 5.
3. Substitute n = 5 into the general formula: C_5H_{2(5)+2}.
4. Calculate the number of hydrogen atoms: 2(5) + 2 = 12.
5. Write the molecular formula for pentane as C_5H_{12}.

Key Concepts

Alkanes

Alkanes are a class of hydrocarbons characterized by single bonds between carbon atoms. They follow the general formula CnH2n+2, where 'n' represents the number of carbon atoms. This structure results in saturated compounds, meaning they contain the maximum number of hydrogen atoms possible for a given number of carbon atoms.

Molecular Formula

The molecular formula of a compound indicates the number and types of atoms present in a molecule. For alkanes, the molecular formula can be derived from the number of carbon atoms in the chain. For pentane, which has five carbon atoms, the molecular formula can be calculated using the formula CnH2n+2.

Carbon Chain Length

The length of the carbon chain in alkanes directly influences their molecular formula and properties. In the case of pentane, the chain consists of five carbon atoms, which determines the specific arrangement and number of hydrogen atoms. Understanding the relationship between chain length and molecular formula is essential for identifying and naming alkanes.