Final answer:
In chemistry, 'species' refers to different forms or variations of a compound. For glycine, the species can refer to glycine hydrochloride or glycine titrated with NaOH.
Step-by-step explanation:
In the context of your question, when they mentioned 'species', they are referring to the different forms or variations of the compound glycine.
In chemistry, the term 'species' is used to describe different chemical entities or compounds that exist under specific conditions.
For example, in the case of glycine hydrochloride (i), the species would refer to the compound when it is combined with hydrochloric acid. Similarly, for glycine titrated with NaOH (ii), the species would refer to the compound when it is being titrated with sodium hydroxide.