Question

Classify each compound as organic or inorganic $$ \text { a. }\mathrm{CaCO}_{3} \quad \text { b. } C_{4} \mathrm{H}_{8} \quad \text { c. }\mathrm{c}_{4} \mathrm{H}_{6} \mathrm{O}_{6} \quad \text {d. LiF} $$

Short answer

a. CaCO3 is inorganic, b. C4H8 is organic, c. C4H6O6 is organic, d. LiF is inorganic.

Step-by-step solution

Define Organic Compounds

Organic compounds are primarily made of carbon atoms bonded with other elements such as hydrogen, oxygen, nitrogen, sulfur, or halogens, and typically include a carbon-hydrogen bond (C-H) as part of their structures.

Identify Organic Compounds

Look for compounds that contain carbon atoms bonded to hydrogen atoms to identify organic compounds. C4H8 (b) and C4H6O6 (c) have both carbon and hydrogen atoms in their structure, making them organic compounds.

Define Inorganic Compounds

Inorganic compounds are generally composed of elements other than carbon or do not have carbon-hydrogen bonds that are characteristic of organic compounds.

Identify Inorganic Compounds

Find compounds that do not primarily contain carbon-hydrogen bonds. CaCO3 (a) and LiF (d) do not have carbon-hydrogen bonds and are thus classified as inorganic compounds.

Key concepts

Understanding Chemical Bonding

Chemical bonding is at the heart of understanding the distinction between organic and inorganic compounds. At a fundamental level, a chemical bond is the force that holds atoms together in a molecule or a compound. Bonds are formed due to the interaction between the valence electrons of atoms, which can be shared or transferred to achieve stabilization.

There are three major types of chemical bonds: ionic bonds, which form when electrons are transferred from one atom to another; covalent bonds, where electrons are shared between atoms; and metallic bonds, which are specific to metal atoms. When considering organic and inorganic compounds, the focus is often on covalent bonds—particularly those involving carbon atoms.

In conducting chemical bonding analysis for classification, remember that the presence of a carbon atom is not enough to deem a compound organic; it must also contain a carbon-hydrogen bond.

The Significance of the Carbon-Hydrogen Bond

The carbon-hydrogen (C-H) bond is a strong indicator of an organic compound. This bond is a type of covalent bond where a single electron from a carbon atom and a single electron from a hydrogen atom are shared to fill their outer electron shells.

Organic chemistry is often called the 'chemistry of life' because C-H bonds are ubiquitous in biological molecules. They form the backbone of many complex structures from simple hydrocarbons to large biomolecules like proteins and DNA.

Here's a key tip: When identifying a carbon-hydrogen bond, look for a straightforward pairing of carbon (C) with hydrogen (H) in a compound's molecular formula. This simple but powerful approach is central to classifying compounds correctly.

Classification of Compounds

To classify compounds as organic or inorganic effectively, it's crucial to understand their elemental composition and bonding. Organic compounds are characterized by the presence of carbon atoms bonded to hydrogen atoms, forming the C-H bond mentioned earlier. However, not all compounds with carbon are organic. For a compound to be classified as organic, it generally must contain carbon bonded to hydrogen.

On the other hand, inorganic compounds typically do not contain carbon-hydrogen bonds. They may, however, contain carbon, such as calcium carbonate (CaCO3). Inorganic compounds can also be largely composed of other elements and may include metals, as we see with lithium fluoride (LiF).

Lastly, while analyzing compounds, it’s beneficial to remember that exceptions can occur due to the vast diversity of chemical substances. Some carbon-containing compounds, like carbonates and oxides, are considered inorganic despite having carbon. In conclusion, the difference between organic and inorganic compounds lies not just in their composition but also in their structure and chemical bonding.