Also known as the Pearson product-moment correlation coefficient, the correlation coefficient (r) measures the linear relationship between two variables, with a value range of -1 to 1. A value close to 1 indicates there is a strong positive linear correlation between two variables; that is, when one variable increases so does the other.
A short definition. Delta H of a reaction is the enthalpy of reaction. H of products minus H of reactants. Each compound has a delta H of formation (dHf). The heats of formation for each substance in a reaction can be added together to compute the energy change for a reaction.
1 D G o (a delta G, with a superscript o), is the free energy change for a reaction, with everything in the standard states (gases at 1 bar, and solutions at 1 M concentration), and at a specific temperature (usually 25Â°C). It is important to distinguish between them. 2  D G o (a delta G, with a superscript o), is the free energy change for a reaction, with everything in the standard states (gases at 1 bar, and solutions at 1 M concentration), and at a specific temperature (usually 25Â°C). 3  D G (just delta G).