Question

The bond energy (in \(\mathbf{k c a l} \mathbf{m o l}^{-1}\) ) of a C-C single bond is approximately A) 1 B) 10 C) 100 D) 1000

Short answer

The bond energy of a C-C single bond is approximately 100 kcal/mol, which corresponds to option C.

Step-by-step solution

Understanding Bond Energy

Bond energy is a measure of the strength of a chemical bond. It is defined as the amount of energy required to break one mole of the bond in the gas phase and it correlates with the bond length and bond dissociation energy.

Identifying the Bond Energy of a C-C Single Bond

By referring to chemical handbooks or bond energy tables, the bond energy for a carbon-carbon (C-C) single bond can be found. For commonly encountered C-C single bonds, the bond energy is approximately 83 to 85 kcal/mol, which is in the range of answer C.

Choosing the Correct Option

Based on the range of typical bond energies for a C-C single bond, the best approximate value from the options provided is 100 kcal/mol.

Key concepts

Chemical Bonds

Chemical bonds are the forces that hold atoms together in molecules and compounds, creating the diverse range of substances we encounter. At their core, chemical bonds are the result of attractions between the positively charged nuclei of atoms and the negatively charged electrons that orbit around them. There are three main types of chemical bonds: ionic bonds, covalent bonds, and metallic bonds.

Ionic bonds form when electrons are transferred from one atom to another, leading to the creation of ions that attract each other due to opposite charges. Covalent bonds involve the sharing of electrons between atoms, allowing them to achieve a more stable electronic configuration. Finally, metallic bonds occur in metals, with a 'sea' of electrons flowing around a lattice of positive metal ions, giving rise to properties like conductivity.

Understanding chemical bonds is fundamental to studying chemistry as they determine the structure and properties of substances. For instance, the nature of the bonds in a substance can affect its boiling and melting points, electrical conductivity, and its ability to engage in chemical reactions.

Bond Dissociation Energy

Bond dissociation energy is a specific measure of bond strength. It is the energy required to break a particular bond in a molecule, where the molecule is in the gaseous state. This process results in the formation of two separate atoms or radicals, each with one of the shared electrons from the original bond. The bond dissociation energy is usually given in units of kilocalories per mole (kcal/mol) or kilojoules per mole (kJ/mol).

It's important to note that bond dissociation energies are average values because the energy required can vary depending on the chemical environment of the bond. Factors such as adjacent atoms, overall molecular structure, and the presence of other bonds can influence bond dissociation energy. Consequently, bond dissociation energy provides insight into the stability of a molecule; the higher the energy, the more stable the bond is against chemical reactions. This concept is crucial when predicting the reactivity of compounds and understanding reaction mechanisms.

C-C Single Bond

The C-C single bond is a fundamental connection between two carbon atoms involving the sharing of a pair of electrons, one contributed by each carbon atom. This type of covalent bond is substantial due to its role in forming the backbone of organic compounds, ranging from simple hydrocarbons to complex biomolecules.

The bond energy associated with a C-C single bond is a reflection of the energy required to break it. The energy for breaking a C-C single bond typically falls within the range of 83-85 kcal/mol, demonstrating the relative stability of these bonds. The strength of this bond is not only a factor of its bond dissociation energy but also depends on the surrounding molecular structure, which can affect the electron distribution and consequently the bond length and strength.

In the context of an educational exercise, identifying the bond energy of a C-C single bond is fundamental for understanding organic chemistry reactions and the stability of carbon-based compounds. When approaching similar exercises, it is always best to consult established reference tables for the most accurate values.