Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange


A tag is a keyword or label that categorizes your question with other, similar questions. Using the right tags makes it easier for others to find and answer your question.

× 140
Questions on the harmful effects of various substances on the human body, or biological organisms in general.
× 136
an analytical technique which takes advantage of the mass-to-charge ratio of gas-phase ions in order to elucidate the composition of a sample.
× 133
highly reactive species, that have one or more unpaired electrons. Whether a species has unpaired electron(s) can be experimentally determined through electron pair resonance spectroscopy…
× 132
For questions about the dipole moment of a bond or a molecule; its calculation, comparison with other bonds or molecules, affect on molecular properties, etc.
× 132
For questions about purification - the process of rendering something pure, clean of foreign or undesired elements. Not to be confused with [metallurgy] or [chromatography].
× 131
should be applied to questions about structural diagrams - diagrams used to show the crude location of possible existent bonds and lone pairs of electrons in a chemical species. Do not use th…
× 129
Questions regarding the development and exploration of chemical ideas, innovations, and discoveries.
× 129
Questions about how the atomic orbitals of the dissociated atoms combine to give individual chemical bonds when a molecule is formed.
× 128
A method to measure how much a chemical substance absorbs light by measuring the intensity of light as a beam of light passes through sample solution.
× 128
For questions about the definition and usage of units of measurement.
× 127
a quantum mechanical model used to estimate the electronic structure of molecules and condensed matter. In broad terms, DFT works by treating all the electrons in th…
× 126
For questions regarding the separation process consisting in the separation of a substance from a matrix. This tag can be used for generic extraction of elements from ore or more specific types of ext…
× 119
A material's ability to conduct electric current or thermal energy by any means.
× 116
For questions relating to the structures, properties, production methods and potential hazards of polymer materials commonly known as plastics
× 114
Questions asking for identification of compounds in photos, by description, or given by a formula.
× 113
For questions related to the chemical reactions and processes that result in a chemical reaching its solid phase.
× 112
For questions about the valence shell electron pair repulsion (VSEPR) theory, in topics of: estimation of bond length, bond angle, bond energy, etc.; determining hybridization of atoms, or shape and g…
× 110
For questions about the reduction potential (A measure of the tendency of a chemical species to acquire electrons and thereby be reduced) or its applications. Also see the tag [electrochemistry].
× 110
Questions related to the chemical and physical influences that influence the rate and probability of chemical reactions. Not to be confused with [catalysis] or [reaction-mechanism].
× 109
substances or combinations used to diagnose, cure, treat, or prevent disease.
× 107
Hydrolysis refers to any reaction with water. For example, it may be said that ammonia hydrolyzes in water to produce ammonium ion and hydroxide ion.
× 104
For questions about the synthesis, properties, and reactions of ester compounds, both organic and inorganic.
× 103
For questions concerning compounds possessing rings with two or more different types of atoms.
× 102
should be applied to questions about the various allotropes of carbon and their physical or chemical properties. Most important modifications are diamond, graphite, fullerenes, graphene and n…
× 102
should only be applied where the effects are specifically related to variance in mass number with the same atomic number (existence of isotopes). Examples include: radioactivity and other nuc…
× 100
The ionization energy of an atom or molecule describes the minimum amount of energy required to remove an electron from the atom or molecule in the gaseous state. Do not confuse with [electron-affinit…
× 100
For questions involving (theoretical or experimental) comparison of density of elements or substances, calculating density of solutions, effects of temperature on density, and other chemical aspects o…
× 99
For questions about cleaning agents and methods used to remove dirt, stains, residues, and bad smells, including proper waste disposal. For particular questions about surfactants, use [tag:surfactants…
× 99
Questions related to color as well as the reflecting and refracting properties of chemicals.
× 98
for questions regarding the principles and application of infrared spectroscopy.
× 98
For questions that deal with possible errors in a specific statement of a specified book, article, website, etc. These questions should always include a complete reference (see tag wiki for format).
× 97
For questions about determining the paramagnetism, diamagnetism, etc. of chemical species and other chemical applications of magnetism. Note that questions oriented towards physical aspects of electro…
× 93
For questions relating to the synthesis of supramolecular, or colloidal structures and their properties or manufacturing processes of characterization for nano-featured structures.
× 93
For questions involving electricity in the scope of chemistry. Note that questions about electrical circuits, semi-conductor diodes, etc. are off topic and more suited for EE.SE or Phy.SE.
× 93
Cheminformatics involves the production, processing, filtering, and searching of chemical information. This includes chemical databases, computational screening, searching, etc.
× 91
Questions relating to radioactive substances and the chemistry of radioactivity. Also, use [rare-earth-elements] if the question is about their radioactivity specifically.