( ( Balancing ( chemical equations ) ) ( literally ( ( means ( counting ( ( the number ) ( of ( times ( ( atom symbols ) ( ( appear ( in ( the ( ( reactants and ) products ) ) ) ) ( to ( make ( sure ( ( the counts ) ( are ( ( the same ) ( on ( both sides ) ) ) ) ) ) ) ) ) ) ) ) ) ) ) . ) ) )
(ROOT (S (NP (VBG Balancing) (NN chemical) (NNS equations)) (ADVP (RB literally)) (VP (VBZ means) (S (VP (VBG counting) (NP (NP (DT the) (NN number)) (PP (IN of) (NP (NP (NNS times)) (SBAR (S (NP (NN atom) (NNS symbols)) (VP (VBP appear) (PP (IN in) (NP (DT the) (NNS reactants) (CC and) (NNS products))) (S (VP (TO to) (VP (VB make) (ADJP (JJ sure) (SBAR (S (NP (DT the) (NNS counts)) (VP (VBP are) (NP (NP (DT the) (JJ same)) (PP (IN on) (NP (DT both) (NNS sides)))))))))))))))))))) (. .)))
Balancing chemical equations literally means counting the number of times atom symbols appear in the reactants and products to make sure the counts are the same on both sides.
(ROOT (S (NP (NNS Atoms)) (VP (VBP make) (NP (NNS products)) (PP (IN by) (S (VP (VBG rearranging) (NP (PRP$ their) (NN chemical) (NNS bonds)) (PP (IN in) (NP (DT a) (NN reactant))))))) (. .)))