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15.3: Appendix C- Symbols for Physical Quantities

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    23775
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     \( \newcommand{\degC}{^\circ\text{C}} % degrees Celsius\)
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     \( \newcommand{\Pa}{\units{Pa}}\)
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     \( \newcommand{\V}{\units{V}}  % volts\)
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     \( \newcommand{\Cpm}{C_{p,\text{m}}} % molar heat capacity at const.p\)
     \( \newcommand{\kT}{\kappa_T} % isothermal compressibility\)
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     \( \newcommand{\bd}{_{\text{b}}}  % subscript b for boundary or boiling point\)
     \( \newcommand{\C}{_{\text{C}}}  % subscript C\)
     \( \newcommand{\f}{_{\text{f}}}  % subscript f for freezing point\)
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     \( \newcommand{\mbB}{_{m,\text{B}}}       % m basis, B\)
     \( \newcommand{\kHi}{k_{\text{H},i}}      % Henry's law constant, x basis, i\)
     \( \newcommand{\kHB}{k_{\text{H,B}}}      % Henry's law constant, x basis, B\)
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     \( \newcommand{\diss}{\subs{diss}} % dissipation\)
     \( \newcommand{\el}{\subs{el}} % electrical\)
     \( \newcommand{\cell}{\subs{cell}} % cell\)
     \( \newcommand{\As}{A\subs{s}} % surface area\)
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     \( \newcommand{\Ej}{E\subs{j}} % liquid junction potential\)
     \( \newcommand{\mue}{\mu\subs{e}} % electron chemical potential\)
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    This appendix lists the symbols for most of the variable physical quantities used in this e-book. The symbols are those recommended in the IUPAC Green Book (Ian Mills et al, Quantities, Units and Symbols in Physical Chemistry, 2nd edition, Blackwell, Oxford, 1993) except for quantities followed by an asterisk (\(^*\)). The first table lists Roman letter symbols, and the second lists Greek letter symbols.

    \begin{array}{lll} \hline \textbf{Symbol} & \textbf{Physical quantity} & \textbf{SI unit} \\ \hline A & \tx{Helmholtz energy} & \tx{J} \\ \As & \tx{surface area} & \tx{m}^2 \\ a & \tx{activity} & \tx{(dimensionless)} \\ B & \tx{second virial coefficient} & \tx{m}^3 \tx{ mol}^{-1} \\ C & \tx{number of components}^* & \tx{(dimensionless)} \\ C_p & \tx{heat capacity at constant pressure} & \tx{J K}^{-1} \\ C_V & \tx{heat capacity at constant volume} & \tx{J K}^{-1} \\ c & \tx{concentration} & \tx{mol m}^{-3} \\ E & \tx{energy} & \tx{J} \\ & \tx{electrode potential} & \tx{V} \\ \boldsymbol{E} & \tx{electric field strength} & \tx{V m}^{-1} \\ E\cell & \tx{cell potential} & \tx{V} \\ \Ej & \tx{liquid junction potential} & \tx{V} \\ E\sys & \tx{system energy in a lab frame} & \tx{J} \\ F & \tx{force} & \tx{N} \\ & \tx{number of degrees of freedom}^* & \tx{(dimensionless)} \\ \fug & \tx{fugacity} & \tx{Pa} \\ g & \tx{acceleration of free fall} & \tx{m s}^{-2} \\ G & \tx{Gibbs energy} & \tx{J} \\ h & \tx{height, elevation} & \tx{m} \\ H & \tx{enthalpy} & \tx{J} \\ \boldsymbol{H} & \tx{magnetic field strength} & \tx{A m}^{-1} \\ I & \tx{electric current} & \tx{A} \\ I_m & \tx{ionic strength, molality basis} & \tx{mol kg}^{-1} \\ I_c & \tx{ionic strength, concentration basis} & \tx{mol m}^{-3} \\ K & \tx{thermodynamic equilibrium constant} & \tx{(dimensionless)} \\ K\subs{a} & \tx{acid dissociation constant} & \tx{(dimensionless)} \\ K_p & \tx{equilibrium constant, pressure basis} & \tx{Pa}^{\sum\nu} \\ K\subs{s} & \tx{solubility product} & \tx{(dimensionless)} \\ \kHi & \tx{Henry’s law constant of species }i, \\ & \quad \tx{mole fraction basis} & \tx{Pa} \\ k_{c,i} & \tx{Henry’s law constant of species }i, \\ & \quad \tx{concentration basis}^* & \tx{Pa m}^3\tx{ mol}^{-1} \\ k_{m,i} & \tx{Henry’s law constant of species }i, \\ & \quad \tx{molality basis}^* & \tx{Pa kg mol}^{-1} \\ l & \tx{length, distance} & \tx{m} \\ L & \tx{relative partial molar enthalpy}^* & \tx{J mol}^{-1} \\ M & \tx{molar mass} & \tx{kg mol}^{-1} \\ \boldsymbol{M} & \tx{magnetization} & \tx{A m}^{-1} \\ M\subs{r} & \tx{relative molecular mass (molecular weight)} & \tx{(dimensionless)} \\ m & \tx{mass} & \tx{kg} \\ m_i & \tx{molality of species }i & \tx{mol kg}^{-1} \\ N & \tx{number of entities (molecules, atoms, ions,} \\ & \quad \tx{formula units, etc.)} & \tx{(dimensionless)} \\ n & \tx{amount of substance} & \tx{mol} \\ P & \tx{number of phases}^* & \tx{(dimensionless)} \\ p & \tx{pressure} & \tx{Pa} \\ & \tx{partial pressure} & \tx{Pa} \\ \boldsymbol{P} & \tx{dielectric polarization} & \tx{C m}^{-2} \\ Q & \tx{electric charge} & \tx{C} \\ Q\sys & \tx{charge entering system at right conductor}^* & \tx{C} \\ Q\subs{rxn} & \tx{reaction quotient}^* & \tx{(dimensionless)} \\ q & \tx{heat} & \tx{J} \\ R\el & \tx{electric resistance}^* & \Omega \\ S & \tx{entropy} & \tx{J K}^{-1} \\ s & \tx{solubility} & \tx{mol m}^{-3} \\ & \tx{number of species}^* & \tx{(dimensionless)} \\ T & \tx{thermodynamic temperature} & \tx{K} \\ t & \tx{time} & \tx{s} \\ & \tx{Celsius temperature} & \degC \\ U & \tx{internal energy} & \tx{J} \\ V & \tx{volume} & \tx{m}^3 \\ v & \tx{specific volume} & \tx{m}^3\tx{ kg}^{-1} \\ & \tx{velocity, speed} & \tx{m s}^{-1} \\ w & \tx{work} & \tx{J} \\ & \tx{mass fraction (weight fraction)} & \tx{(dimensionless)} \\ w\el & \tx{electrical work}^* & \tx{J} \\ w' & \tx{nonexpansion work}^* & \tx{J} \\ x & \tx{mole fraction in a phase} & \tx{(dimensionless)} \\ & \tx{Cartesian space coordinate} & \tx{m} \\ y & \tx{mole fraction in gas phase} & \tx{(dimensionless)} \\ & \tx{Cartesian space coordinate} & \tx{m} \\ Z & \tx{compression factor (compressibility factor)} & \tx{(dimensionless)} \\ z & \tx{mole fraction in multiphase system}^* & \tx{(dimensionless)} \\ & \tx{charge number of an ion} & \tx{(dimensionless)}\\ & \tx{electron number of cell reaction} & \tx{(dimensionless)} \\ & \tx{Cartesian space coordinate} & \tx{m} \\ \hline \end{array}

    \begin{array}{lll} \hline \textbf{Symbol} & \textbf{Physical quantity} & \textbf{SI unit} \\ \hline \alpha & \tx{degree of reaction, dissociation, etc.} & \tx{(dimensionless)} \\ & \tx{cubic expansion coefficient} & \tx{K}^{-1} \\ \g & \tx{surface tension} & \tx{N m}^{-1}, \tx{J m}^{-2} \\ \g_i & \tx{activity coefficient of species i,} \\ & \quad \tx{pure liquid or solid standard state}^* & \tx{(dimensionless)} \\ \g_{m,i} & \tx{activity coefficient of species i,} \\ & \quad \tx{molality basis} & \tx{(dimensionless)} \\ \g_{c,i} & \tx{activity coefficient of species i,} \\ & \quad \tx{concentration basis} & \tx{(dimensionless)} \\ \g_{x,i} & \tx{activity coefficient of species i,} \\ & \quad \tx{mole fraction basis} & \tx{(dimensionless)} \\ \g_{\pm} & \tx{mean ionic activity coefficient} & \tx{(dimensionless)} \\ \G & \tx{pressure factor (activity of a reference state)}^* & \tx{(dimensionless)} \\ \epsilon & \tx{efficiency of a heat engine} & \tx{(dimensionless)} \\ & \tx{energy equivalent of a calorimeter}^* & \tx{J K}^{-1} \\ \vartheta & \tx{angle of rotation} & \tx{(dimensionless)} \\ \kappa & \tx{reciprocal radius of ionic atmosphere} & \tx{m}^{-1} \\ \kappa _T & \tx{isothermal compressibility} & \tx{Pa}^{-1} \\ \mu & \tx{chemical potential} & \tx{J mol}^{-1} \\ \mu\subs{JT} & \tx{Joule–Thomson coefficient} & \tx{K Pa}^{-1} \\ \nu & \tx{number of ions per formula unit} & \tx{(dimensionless)} \\ & \tx{stoichiometric number} & \tx{(dimensionless)} \\ \nu_+ & \tx{number of cations per formula unit} & \tx{(dimensionless)} \\ \nu_- & \tx{number of anions per formula unit} & \tx{(dimensionless)} \\ \xi & \tx{advancement (extent of reaction)} & \tx{mol} \\ \varPi & \tx{osmotic pressure} & \tx{Pa} \\ \rho & \tx{density} & \tx{kg m}^{-3} \\ \tau & \tx{torque}^* & \tx{J} \\ \phi & \tx{fugacity coefficient} & \tx{(dimensionless)} \\ & \tx{electric potential} & \tx{V} \\ \Del\phi & \tx{electric potential difference} & \tx{V} \\ \phi_m & \tx{osmotic coefficient, molality basis} & \tx{(dimensionless)} \\ \varPhi_L & \tx{relative apparent molar enthalpy of solute}^* & \tx{J} mol^{-1} \\ \omega & \tx{angular velocity} & \tx{s}^{-1} \\ \hline \end{array}


    This page titled 15.3: Appendix C- Symbols for Physical Quantities is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by Howard DeVoe via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.