Interview Questions and Answers

The Aufbau principle states that electrons fill orbitals in order of increasing energy, starting with the lowest energy level.

Example:

For carbon (C), the electron configuration is 1s² 2s² 2p², following the Aufbau principle.

Entropy is a measure of the disorder or randomness in a system. In thermodynamics, systems tend to move towards higher entropy.

Example:

Melting ice increases entropy as the solid structure becomes more disordered.

The Pauli exclusion principle states that no two electrons in an atom can have the same set of four quantum numbers.

Example:

In an orbital, electrons must have opposite spins to obey the Pauli exclusion principle.

Gibbs free energy is a thermodynamic potential that measures the maximum reversible work that can be performed by a system at constant temperature and pressure.

Example:

A negative ΔG indicates a spontaneous reaction.

The Heisenberg uncertainty principle states that it is impossible to simultaneously know both the exact position and momentum of a particle with absolute certainty.

Example:

The more accurately we measure a particle's position, the less accurately we can know its momentum, and vice versa.

Endergonic reactions require an input of energy to proceed, while exergonic reactions release energy.

Example:

Photosynthesis is an endergonic process, absorbing sunlight to produce glucose. Cellular respiration is exergonic, releasing energy from glucose.

Photochemical reactions are chemical reactions that are initiated by the absorption of light. They often involve the breaking or formation of bonds.

Example:

Photosynthesis is a photochemical process where light energy is used to convert carbon dioxide and water into glucose and oxygen.

Chirality refers to the property of molecules that are non-superimposable on their mirror images. Chiral molecules often have a central asymmetric carbon atom.

Example:

The amino acid alanine is chiral, with a central carbon bonded to four different groups (H, NH2, COOH, and a side chain).

The Heisenberg uncertainty principle states that it is impossible to simultaneously know both the exact position and momentum of a particle with absolute certainty.

Example:

The more accurately we measure a particle's position, the less accurately we can know its momentum, and vice versa.