( ( In ( ( ( this classification ) , ) ( which ( is ( ( the basis ) ( of ( ( the ( modern concept ) ) ( of electronegativity ) ) ) ) ) ) ) ) ( , ( oxygen ( ( was ( ( ( the ( most ( strongly negative ) ) ) and ) ( potassium ( the ( most ( strongly positive ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (NP (DT this) (NN classification)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBZ is) (NP (NP (DT the) (NN basis)) (PP (IN of) (NP (NP (DT the) (JJ modern) (NN concept)) (PP (IN of) (NP (NN electronegativity))))))))))) (, ,) (NP (NN oxygen)) (VP (VBD was) (NP (NP (DT the) (ADJP (RBS most) (RB strongly) (JJ negative))) (CC and) (NP (NP (NN potassium)) (NP (DT the) (ADJP (RBS most) (RB strongly) (JJ positive)))))) (. .)))
In this classification, which is the basis of the modern concept of electronegativity, oxygen was the most strongly negative and potassium the most strongly positive.
(ROOT (S (NP (NNP Oxygen)) (VP (VBZ is) (NP (NP (DT the) (NN name)) (PP (IN of) (NP (DT the) (JJ second) (ADJP (RBS most) (JJ electronegative)) (NN element))))) (. .)))