The scientific method

Nitrogen (n), phosphorus (p), and potassium (k) are the main nutrients in plant fertilizers. according to an industry convention, the numbers on the label refer to the mass percents of n, p2o5, and k2o, in that order. calculate the n: p: k ratio of a 30: 10: 10 fertilizer in terms of moles of each element, and express it as x: y: 1.0.

An observation that requires measurement is called quantitative observable or qualitative

To find the enthalpy of a reaction in the lab, you measured the of the reactants and the change during the reaction.