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Notation used in chemical equations, apparatus diagrams and physical constants.
All 270symbols recorded in this context, A–Z.
A capital K with a lowercase a subscript.
An italic capital S, the integral of the Lagrangian over time.
A Greek gamma, correcting concentration to effective concentration.
An italic capital Y, the reciprocal of impedance.
A sign for a water bath, giving gentle and controlled heat.
A capital F marking points on every face.
A fixed frame for the body.
A Greek omega, radians per second rather than cycles per second.
A capital L, rotational momentum about an axis.
A plain lowercase a, removing one quantum.
A Greek alpha or beta — a small curved letter — before a sugar's name.
An overbar marking a particle's antimatter counterpart.
Standard outlines for flasks, condensers and joints.
The letters aq in brackets after a formula.
Coordinate ranges bounding the smallest unique part.
A name and a date after a species.
A capital N with subscript A, the number of entities in a mole.
A dashed line marking a glide along an axis.
A unit of area for nuclear reaction probability.
An italic capital B, one third per quark.
A straight-sided cylinder with a pouring lip.
A circle inside a hexagon, standing for delocalised electrons.
A hexagon with an inscribed circle, representing delocalised aromatic bonding.
A trefoil of overlapping circles, designed to be instantly recognisable as a warning for biological hazards.
A number from one to four rating containment.
A capital I marking a lattice point at the cell centre.
A Greek mu with a capital B subscript, the electron's magnetic unit.
An italic a with a nought subscript, the atomic length scale.
A wider tube for heating larger quantities.
An italic k, often subscripted B, relating temperature to energy.
Angle brackets and a bar denoting quantum states.
Four figures used for hexagonal crystals.
A theta with a B subscript, the angle of complete polarisation.
A Greek mu with a raised numeral, before a ligand's name.
A flat perforated plate above a stem.
A vertical barrel on a base with a gas inlet.
A long graduated tube with a tap at its foot.
Digits in three hyphen-separated groups, the last a single check digit.
A formula written above a reaction arrow, naming a catalyst.
A single upright stroke, marking a phase boundary.
A capital C, swapping every particle for its antiparticle.
A Greek mu, the energy cost of adding one more particle.
A capital gamma with one raised and two lowered indices.
Letters p and q naming the two arms.
Numbers locating a band on an arm.
A del with bracketed position.
An inv with bracketed breakpoints.
A t with bracketed chromosomes and breakpoints.
Plane indices naming a preferred break.
A Greek mu, the ratio of friction to normal force.
An italic capital Z, one for an ideal gas and not otherwise.
Square brackets around a species, meaning its concentration.
A Greek sigma, the reciprocal of resistivity.
A cone-shaped vessel with a narrow neck.
A capital Greek lambda, the energy of empty space.
Three capitals together, a symmetry believed exact.
A lowercase a with a dagger superscript, adding one quantum.
A theta with a c subscript, beyond which light cannot escape.
A figure limiting fissile packages carried together.
A Greek sigma, an effective target area for a reaction.
A descriptive term for external shape.
Three figures in angle brackets naming equivalent directions.
Three figures in square brackets naming a direction.
Three figures in curly brackets naming equivalent planes.
A symbol naming one of thirty-two symmetry classes.
A curved arrow showing where a pair of electrons moves.
A bold capital J, current per unit cross-section.
Small capital D or L before a name, from a sugar's Fischer projection.
A Greek lambda, the probability per second of one nucleus decaying.
A Greek rho with a circumflex, a state that may be a mixture.
A Greek kappa with a raised numeral, before a ligand's name.
A sealed vessel with a plate above a drying agent.
A dash-dot line marking a diagonal glide.
A dash-dot line with arrows for a quarter glide.
A capital D, optical power as a reciprocal metre.
A T-shaped piece carrying a thermometer.
Two strands winding around each other, joined by rungs.
Two parallel lines between atoms, representing a shared double bond.
A dagger with two crossbars, raised after a quantity.
Letters naming which side of a double bond groups sit on.
Twelve views, named by convention.
A capital G with two indices, the geometry side of the field equations.
A bold capital D, the electric field with polarisation folded in.
A script capital E, and not a force at all.
A numeral, a lowercase letter and a raised count, repeated.
An italic lower-case e, the magnitude of the charge on a proton.
A capital delta before an H, denoting heat absorbed or released.
An italic capital H, internal energy plus pressure times volume.
An italic capital S, a measure of how many ways a state can be arranged.
Two half-headed arrows pointing opposite ways, marking a reversible reaction.
A shallow open dish for driving off liquid.
An italic capital F, the charge on a mole of electrons.
Two digits: quadrant then tooth.
Straight, wavy and coiled lines for different particles.
A Greek alpha for a pure number near one over one hundred and thirty-seven.
A cross of straight lines with the vertical bonds going back.
An italic f, the distance from a lens to its focus.
A circled plus or minus on an atom in a structure.
A filled square marking a fourfold axis.
Three fractions locating an atom in a cell.
An italic f, an effective pressure for a real gas.
An enclosure with a sliding sash and extraction.
An italic capital R, the molar gas constant.
An upward arrow after a formula, marking a gas leaving the reaction.
A graduated barrel with a free-moving plunger.
Italics for the gene, upright for the protein.
An image of a substance corroding a surface and a hand, in a red-bordered diamond — the GHS symbol for corrosive hazard.
A black image of a dead fish and tree in a red-bordered diamond, the GHS symbol for aquatic/environmental hazard.
A black exclamation mark in a red-bordered diamond, the GHS symbol for lower-level health/physical hazards or irritation.
A black exploding-bomb icon in a red-bordered diamond, the GHS symbol for explosive hazard.
A black flame above a black circle in a red-bordered diamond, the GHS symbol for oxidizing hazard.
A black flame icon in a red-bordered diamond, the GHS symbol for flammable hazard.
A black gas cylinder icon in a red-bordered diamond, the GHS symbol for gases under pressure.
A capital H followed by three digits.
A black human silhouette with a starburst on the chest, in a red-bordered diamond — the GHS symbol for serious, longer-term health hazards.
A capital P followed by three digits.
A black skull and crossbones in a red-bordered diamond, the GHS symbol for acute toxicity.
An italic capital G, deciding whether a reaction proceeds.
A lowercase g, the carrier of the strong force.
A narrow tube with a scale along its length.
An italic capital G, the constant in Newton's law of gravitation.
A t with subscript one-half, the time for half a quantity to decay.
A scripted or hatted H standing for a system's total energy.
A Greek eta with a raised numeral, before a ligand's name.
A ladder of short lines showing a bond going away.
A flat ring drawn in perspective with substituents up or down.
An italic capital A or F, the constant-volume counterpart of Gibbs energy.
A slip that revises a name.
Symmetry named by axis order and plane letter.
A capital H, the excitation of the field that gives mass.
Carbon first, hydrogen second, then everything alphabetically.
A capital H with a nought subscript, the current expansion rate.
An italic capital Z, resistance extended to alternating current.
A structured string beginning InChI= with slash-separated layers.
A small open circle marking a centre of symmetry.
An italic capital I, treating the proton and neutron as one particle.
An element symbol with mass number above and atomic number below, to its left.
A raised mass number before an element symbol in a formula.
A chromosome complement in one line.
A small tapered vessel for strong heating.
A cone above a narrow stem.
A script capital L, kinetic energy minus potential energy.
A number rating how dangerous a laser is to the eye.
A point group symbol with inversion added.
An italic capital L, counting electrons, muons and taus.
A tube within a water jacket, drawn sloping.
Two dots showing electrons not used in bonding.
A Greek gamma, how much relativity changes things.
A bold capital H, measured in amperes per metre.
A bold capital B, measured in tesla.
A bold capital A, a field whose curl is the magnetic field.
The tallest peak set to one hundred.
A tall graduated cylinder on a wide base.
The italic word meso before a compound's name.
A lowercase g with two lower indices, defining distance itself.
Three figures in round brackets naming a plane.
A bar above a figure marking a negative index.
A heavy solid line marking a mirror.
An italic capital I or J, resistance to angular acceleration.
A p with a circumflex, standing for a derivative times minus i ℏ.
A bold or italic p, mass times velocity.
Two karyotypes separated by an oblique.
A letter and subscript naming a symmetry species.
A circle with three bonds from the centre and three from the rim.
A four-part diamond rating health, fire, reactivity and special hazards.
Letters naming a peak's splitting pattern.
An arrow with a Greek letter naming the decay mode.
A Greek mu with a capital N subscript, the nuclear magnetic unit.
A capital N with a circumflex, counting quanta.
The letters NA, a lens's light-gathering cone.
A plus or minus in brackets before a compound's name.
Roman numerals in brackets naming an element's oxidation state.
A bracket showing the quadrant.
A capital P, reflecting space through the origin.
A lowercase delta with a raised plus or minus.
An italic capital Z, a weighted count of a system's states.
A sigma with a subscript x, y or z, three two-by-two matrices.
Brackets around an individual's symbol.
A symbol carrying a letter for an ongoing pregnancy.
A symbol with an abbreviation beneath.
Lines converging to a single point.
A Greek mu with a nought subscript, the magnetic constant.
A shallow flat dish with an overlapping lid.
A Greek phi or delta, how far into a cycle a wave is.
Subscript letters saying whether a substance is solid, liquid, gas or dissolved.
Branches that mean relatedness, not time.
A lowercase p before a capital K with an a subscript.
An italic lower-case h, denoting the quantum of action.
Peaks labelled with plane indices.
A bold capital S, the direction and rate of energy flow.
A downward arrow after a formula, marking a solid falling out of solution.
A capital P opening a space group symbol.
A Greek tau, the time a clock actually reads.
An italic capital Q, how slowly an oscillator loses energy.
Six lowercase letters u, d, c, s, t and b.
Italic letters naming the handedness of a stereocentre.
A capital R giving agreement as a fraction.
The letters rac or a bracketed plus-minus sign.
A three-bladed trefoil, conventionally black on a yellow background, warning of ionising radiation hazards.
A single dot marking an unpaired electron.
An italic capital X, the imaginary part of impedance.
A single-headed arrow separating reactants from products.
Reagents above an arrow and conditions below it.
A lowercase z, fractional stretching of a wavelength.
A struck-through h, Planck's constant divided by two pi.
A flask with a vertical condenser above it, in an apparatus diagram.
An italic n, how much a medium slows light.
A Greek rho, resistance scaled out of the shape.
A double-headed straight arrow between two drawn structures.
A vertical rod on a heavy base with an adjustable clamp.
A double-shafted open arrow read backwards from the product.
A capital R marking a rhombohedral setting.
A capital R with two indices, a contraction of the Riemann tensor.
A capital R with four indices, the full description of curvature.
A rotation symbol with an open circle inside.
A spherical vessel with a narrow neck.
A capital R with an infinity subscript, the hydrogen spectrum scale.
A transparent barrier between operator and apparatus.
Two upright strokes, marking a junction whose potential is negligible.
Symmetry named by a letter and a subscript.
An r with a subscript s, the size of a black hole's horizon.
A rotation symbol carrying tails.
A pear-shaped vessel with a tap at the base.
Letters stacked by information.
A conical flask with a tube on its neck.
A capital A, B or C marking one centred face pair.
Greek letters naming how orbitals overlap in a bond.
How a number is written to state how well it is known.
A point group symbol with dots for missing directions.
A filled hexagon marking a sixfold axis.
A zigzag of lines whose vertices are carbon atoms, with hydrogens left undrawn.
A single line of letters, digits and brackets encoding a structure.
A capital K with sp as a subscript.
A lattice letter followed by symmetry elements.
An italic lower-case c, denoting the speed of light in vacuum.
Up and down arrows in boxes filling electron orbitals.
An italic k, stiffness in newtons per metre.
A capital E with a nought superscript, in volts.
A small circle, often struck through, raised after a quantity.
A Greek sigma, relating temperature to radiated power.
An italic capital S, counting strange quarks with a sign flip.
A capital F carrying three indices.
An italic capital B, the imaginary part of admittance.
A superscript, a capital letter and a subscript together.
A narrow tube closed with a rounded end.
An ellipsoid drawn for atomic displacement.
A long tube with a bulbous flared top.
A filled triangle marking a threefold axis.
Letters for the faces of a tooth.
A Greek tau, or a capital M in engineering.
A boxed figure on a transport label.
A three-legged stand with a mesh square on top.
A matrix or plane naming a twin relation.
A filled lens shape marking a twofold axis.
Four digits, often on an orange plate.
One to thirty-two, straight through.
An epsilon with a zero subscript, in every electrostatic formula.
A Greek letter numbering a normal mode.
A pear-shaped vessel with a single graduation line.
A tube with a central bulb and one graduation.
A capital W with a charge superscript, the charged weak carrier.
A squeeze bottle with a bent delivery tube.
A shallow circular dish used as a cover or surface.
A Greek psi standing for a quantum state's amplitude.
A Greek lambda, denoting the distance between successive wave peaks.
An italic k or a tilde-topped nu, waves per unit length.
A single wavy line, meaning the configuration is unspecified.
A solid triangle showing a bond coming towards the reader.
A multiplicity figure with a letter.
A capital Z with a nought superscript, the neutral weak carrier.