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.
delta noun (RIVER) âº [ 1  C ] geography an area of low, flat land, sometimes shaped like a triangle, where a river divides into several smaller rivers before flowing into the sea: âº [ 2  C or U ] symbol Î´, Î´ language, mathematics, science the fourth letter of the Greek alphabet.