Question

What is the formula for the alkane decane, which has 10 carbon atoms?

Short answer

The chemical formula for the alkane decane is C10H22.

Step-by-step solution

- Understanding Alkane General Formula

Recognize that alkanes are hydrocarbons with single bonds between carbon atoms. The general formula for alkanes is CnH(2n+2), where 'n' represents the number of carbon atoms.

- Insert Number of Carbon Atoms

The problem states there are 10 carbon atoms, so n=10. Plug this value into the general formula for alkanes.

- Calculate the Number of Hydrogen Atoms

Using the formula CnH(2n+2), calculate the number of hydrogen atoms for n=10: H(2*10+2) = H(20+2) = H22.

- Write the Chemical Formula for Decane

Combine the number of carbon and hydrogen atoms to write the chemical formula for decane: C10H22.

Key concepts

Alkane General Formula

Understanding the general formula of alkanes is fundamental in organic chemistry. Alkanes, a primary type of hydrocarbons, consist solely of hydrogen and carbon atoms, connected by single bonds in a chain.When it comes to decoding the structure of alkanes, you’ll find there’s a simple pattern to follow. The general formula for any alkane is \( C_nH_{2n+2} \) where 'n' is the number of carbon atoms. This streamlined formula stems from the fact that each carbon atom forms four bonds: two with adjacent carbon atoms (or one if it's at the end of the chain) and the rest with hydrogen atoms. As a result, for every carbon atom you have, there will always be two more hydrogen atoms than twice the number of carbons.Let's use decane, which contains 10 carbon atoms, as an example. Applying the general formula, we can determine the number of hydrogen atoms should be \( 2 \times 10 + 2 \), which equals 22. Hence, the chemical formula for decane is \( C_{10}H_{22} \). Remember, this formula is unique to alkanes due to their single-bonded carbon chain structure. Other classes of hydrocarbons, such as alkenes or alkynes, follow different patterns due to the presence of double or triple bonds.

Hydrocarbons

Hydrocarbons serve as the foundation stones of organic chemistry. These organic compounds are composed exclusively of carbon and hydrogen atoms — wonderfully simple, yet incredibly diverse in their structure and properties.The ‘hydro-’ prefix indicates the presence of hydrogen atoms, while ‘-carbon’ obviously points to carbon atoms. Hydrocarbons come in various forms, with alkanes being the most straightforward type, characterized by carbon atoms connected by single bonds. Other types include alkenes and alkynes with double and triple bonds, respectively.The reason why hydrocarbons are so central in chemistry and in the world around us is their versatility. They are the primary constituents of fossil fuels like natural gas, oil, and coal, and are also the basic building blocks from which we construct a vast array of materials, including plastics, medicines, and dyes.Decane, an alkane with the chemical formula \( C_{10}H_{22} \), is one such hydrocarbon. As a relatively simple molecule, its structure and chemical reactions can be predicted using the general rules that govern the behavior of alkanes. Apart from being a topic of academic interest, understanding decane and its equivalents is crucial for industries such as petrochemicals and energy production.

Single Bonds in Carbon Atoms

Carbon atoms are the backbone of organic molecules, and their ability to form single, double, or triple bonds with other atoms, including other carbon atoms, creates a vast array of chemical compounds. In the case of alkanes, the carbon atoms are connected exclusively by single bonds, which are also known as sigma bonds.A single bond is a chemical bond between two atoms involving two electrons — one from each atom — and is the simplest, most fundamental type of covalent bond in chemistry. This bond formation results in a stable electronic configuration for the bonded atoms. When carbon atoms are single-bonded, as they are in alkanes like decane, they form a flexible, not easily breakable chain. The electron pairing in these bonds can rotate, which gives the carbon chain the ability to twist and bend, without breaking.One of the notable characteristics of single bonds between carbon atoms is that they allow for a high degree of freedom in the conformation, or spatial arrangement, of the molecule, which can result in different shapes and, consequently, different physical properties, such as boiling points and melting points.Importantly, these single bonds are also the reason why alkanes are relatively less reactive compared to other hydrocarbons with multiple or triple bonds, since single bonds are more stable and require more energy to break. This stability explains why alkanes like decane are common in the longer-lasting molecules found in lubricants and fuels.