Quantum Mechanics
The branch of physics describing the behavior of matter and energy at atomic and subatomic scales. Quantum mechanics introduces the wave-particle duality of matter, quantization of…
Chemical Glossary — Letter Q
4 chemicals found starting with "Q"
Quantum Numbers
A set of four numbers (n, l, mₗ, ms) that uniquely describe the state of an electron in an atom. The principal quantum number (n) gives energy level; the azimuthal (l) gives orbita…
Quantum Yield
Quantum yield (Φ) is the ratio of the number of events (photons emitted, molecules reacted, electrons produced) to the number of photons absorbed. In photochemistry, it measures th…
Quaternary Ammonium
Quaternary ammonium compounds (QACs) are nitrogen-containing compounds where nitrogen bears four organic groups (R), giving a permanent positive charge (NR₄⁺). Unlike ammonium (NH₄…
About Chemicals Starting With Q
This page lists all chemicals in our database beginning with the letter Q. Each entry provides the chemical formula, CAS registry number, physical and chemical properties, common uses, and safety information. Use the alphabetical navigation above to browse other letters, or use the search function to find a specific chemical quickly.
Our chemical glossary covers acids, bases, salts, organic compounds, inorganic compounds, solvents, and many more categories. Click on any chemical name to view its full detailed profile.