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Symbols Used to Denote a Chemical Reactions and Process or Condition

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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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