Standard molar entropy: Meaning (information, definition, explanation, facts)

In chemistry, the standard molar entropy is the entropy content of one mole of substance, under conditions of standard temperature and pressure. By comparing the entropies of products and reactants in a chemical reaction, we can determine whether the reaction will go forward or backwards. It usually given the symbol S⁰, and the units J/mol·K (joules per kelvin per mole).