# Symbols Used to Denote a Chemical Reactions and Process or Condition

See also Thermodynamic Terms, Functions and Relations

Subscript Symbol | Process |
---|---|

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:

ΔG_{r} : Change in Gibbs free energy by (a given) reaction,

ΔH_{sol} : Change in enthalpy by (a given) solution

ΔS_{vap} : Change in entropy by (a given) evaporation

p^{θ} : Pressure at standard state (normally 1 bar)

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