( ( If ( ( bigger units ) ( are needed ) ) ) ( , ( ( ( ( ( ( ( the kilojoule ) ( -LRB- ( kJ -RRB- ) ) ) ( is used ) ) , ) and ) ( it ( ( 's obviously ) ( 1000 joules ) ) ) ) . ) ) )
(ROOT (S (SBAR (IN If) (S (NP (JJR bigger) (NNS units)) (VP (VBP are) (VP (VBN needed))))) (, ,) (S (NP (NP (DT the) (NN kilojoule)) (PRN (-LRB- -LRB-) (NP (NN kJ)) (-RRB- -RRB-))) (VP (VBZ is) (VP (VBN used)))) (, ,) (CC and) (S (NP (PRP it)) (VP (VBZ 's) (ADVP (RB obviously)) (NP (CD 1000) (NNS joules)))) (. .)))
If bigger units are needed, the kilojoule (kJ) is used, and it's obviously 1000 joules.
(ROOT (S (NP (NNS Kilojoules)) (VP (VBP are) (ADVP (RB typically)) (VP (VBN used) (S (VP (TO to) (VP (VB measure) (NP (NP (NNP heats)) (PP (IN of) (NP (NN reaction))))))))) (. .)))