Her behavior has been reinforced (i.e. strengthened). Reinforcement can be external or internal and can be positive or negative. If a child wants approval from parents or peers, this approval is an external reinforcement, but feeling happy about being approved of is an internal reinforcement.
It remained to define the unit of amount of substance by fixing the corresponding mass of carbon 12; by international agreement, this mass has been fixed at 0.012 kg, and the unit of the quantity amount of substance was given the name mole (symbol mol).
as of 2011 the mole is defined by bipm to be the amount of substance of a system which contains the same number of elementary entities e g atoms molecules ions electrons as atoms in 0 012 kilograms of carbon 12 12 c the isotope of carbon with relative atomic mass 12he mole is not a true metric i e measuring unit rather it is a parametric unit and amount of substance is a parametric base quantity the si defines numbers of entities as quantities of dimension one and thus ignores the ontological distinction between entities and units of continuous quantities