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Symbols Used to Denote a Chemical Reactions and Process or Condition

Explanation of symbols used as subscripts or superscripts to tell more about the type of chemical reaction, process or condition.

See also Thermodynamic Terms, Functions and Relations

Symbols Used to Denote Chemical Reactions or Process Conditions
Subscript SymbolProcess
ads adsorption
at atomization
c combustion reaction
dil dilution (of a solution)
dpl displacement
f formation reaction
fus melting, fusion (solid → liquid)
imm immersion
mix mixing of fluids
r reaction in general
sol solution (of solute in solvent)
sub sublimation (solid → gas)
trs transition (between two phases)
vap vaporization, evaporation (liquid → gas)
Superscript Symbol Process
app apparent
≠, ‡ activated complex, transition state
E excess quantity
id ideal
infinite dilution
* pure substance
°, θ standard

Examples of use could be:

ΔGr : Change in Gibbs free energy by (a given) reaction,

ΔHsol : Change in enthalpy by (a given) solution

ΔSvap : Change in entropy by (a given) evaporation

pθ : Pressure at standard state (normally 1 bar)

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