SAT Subject Test Chemistry,10 edition

Note that it is important not to confuse STP with standard conditions encountered in
thermochemistry—the two standards involve different temperatures and are used for different
purposes. STP (0ºC or 273 K) is generally used for gas law calculations; standard conditions (usually
25ºC or 298 K) is used when measuring standard enthalpy, entropy, Gibbs free energy, and cell
potential.