ɪnðə kˈeɪs ʌv dᵻɹˈɛkt taɪtɹˈeɪʃən, ɪɾ ɪz nˌɑːt nˈɛsᵻsɚɹi tə nˈoʊ ðɪ ɛɡzˈækt ɐmˈaʊnt ʌv wˈiːk ˈæsɪd ˈiː.dʒˈiː. bˈoːɹɪk ˈæsɪd bɪkˈʌz ɪt dʌznˌɑːt ˌɪntəfˈɪɹ wɪððə taɪtɹˈeɪʃən ɪt dˈʌz hæv təbi ɪn ɛksˈɛs ʌv æmˈoʊniə tʊ ɪfˈɪʃəntli tɹˈæp ɪt.
In the case of direct titration, it is not necessary to know the exact amount of weak acid (e.g. boric acid) because it does not interfere with the titration (it does have to be in excess of ammonia to efficiently trap it).