( pH ( ( means ( ( ( the ( negative logarithm ) ) ( -LRB- ( ( base 10 ) -RRB- ) ) ) ( of ( ( the concentration ) ( of ( ( hydrogen ions ) ( in ( a solution ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NN pH)) (VP (VBZ means) (NP (NP (NP (DT the) (JJ negative) (NN logarithm)) (PRN (-LRB- -LRB-) (NP (NN base) (CD 10)) (-RRB- -RRB-))) (PP (IN of) (NP (NP (DT the) (NN concentration)) (PP (IN of) (NP (NP (NN hydrogen) (NNS ions)) (PP (IN in) (NP (DT a) (NN solution))))))))) (. .)))
pH means the negative logarithm (base 10) of the concentration of hydrogen ions in a solution.
(ROOT (S (NP (NP (DT The) (NN concentration)) (PP (IN of) (NP (NP (DT the) (NN hydrogen) (NN ion)) (PP (IN in) (NP (DT a) (NN solution)))))) (VP (MD can) (VP (VB be) (VP (VBN calculated) (SBAR (WHADVP (WRB when)) (S (NP (DT the) (NN ph)) (VP (VBZ is) (VP (VBN known)))))))) (. .)))
The concentration of the hydrogen ion in a solution can be calculated when the ph is known.