Question

Which of the following bond orders is indication of existence of a molecule? (a) Zero bond order (b) Negative boad order (c) Positive bond order (d) All of these.

Short answer

A positive bond order is an indication of the existence of a molecule.

Step-by-step solution

Understanding Bond Order

Bond order refers to the number of chemical bonds between a pair of atoms. A positive bond order indicates the existence of a stable bond. A zero bond order means there are no bonds between the atoms, implying no molecule. A negative bond order is not physically meaningful, as bonds cannot be less than zero.

Identifying the Correct Bond Order for a Molecule's Existence

Only a positive bond order is associated with the existence of a molecule because it signifies that there is at least one bond holding the atoms together.

Eliminating Incorrect Options

The options with zero or negative bond order can be eliminated because they do not suggest the presence of a bond or a molecule.

Key concepts

Understanding Chemical Bonds

What exactly are chemical bonds? Essentially, they're the glue that holds atoms together in molecules. When we reference chemical bonds, we're talking about the attractive forces that arise due to the interactions between electrons and nuclei of different atoms. Three main types of chemical bonds exist: ionic, covalent, and metallic.

Ionic bonds form between atoms that transfer electrons, with one atom giving up electrons (becoming a positive ion) and the other gaining electrons (becoming a negative ion). Covalent bonds occur when two atoms share pairs of electrons, which can be in single, double, or triple bonds. Metallic bonds are found in metals, where electrons are not associated with individual atoms but are free to move throughout the entire structure.

Understanding chemical bonds is crucial because they dictate the properties of substances, such as boiling and melting points, conductivity, and solubility. These properties are important in the study of chemistry and in various applications in everyday life and industry.

Molecular Stability

Why are some molecules more stable than others? The answer lies in the concept of molecular stability, which is closely tied to the arrangement of atoms within a molecule and the strength of the bonds that hold these atoms together.

Electron Configuration and Stability

Atoms strive for a stable electron configuration, often achieved by completing an outer electron shell, which typically leads to more stable molecules. The bond strength also influences stability; stronger bonds (like covalent bonds) can increase molecular stability.

Energy Considerations

Another perspective is the energy standpoint where stable molecules have lower potential energy. Energy is released when a bond is formed, which stabilizes the system. If a molecule requires a high energy input to break its bonds, it's considered more stable.

In summary, molecular stability is essential for understanding reactions and processes in chemistry, such as why certain reactions occur spontaneously while others do not, and it helps in predicting the behavior of substances under different conditions.

Significance of Bond Order

Now, let's delve into bond order and its significance. As we explored in the step-by-step solution, bond order is a good indicator of a molecule's stability and the strength of the chemical bonds present. It is calculated as the number of bonding electrons minus the number of anti-bonding electrons, divided by two.

A higher bond order often means a stronger bond. For example, a double bond (bond order of 2) is stronger and shorter than a single bond (bond order of 1). This directly correlates to bond energy; higher bond orders mean higher bond energies and thus more stable molecules.

When assessing molecular existence, a positive bond order is key. It signifies that there are sufficient bonding interactions to hold the atoms together as a molecule. Zero or negative bond orders indicate either a lack of bonding or an unstable arrangement of electrons, which cannot sustain a stable molecule. Therefore, understanding bond order is crucial for predicting chemical reactivity, the form and structure of molecules, and their physical and chemical properties.