Kimyo bakalavr) 2021-2022 o’quv yili I semester uchun II kurs (III semestr) namangan – 2021

Ruxning birlamchi standart eritmasi yordamida

EDTA eritmasini standartlash

Titrlash kolbasiga ruxning standart eritmasidan alikvot qism olinadi, ustiga 20 ml pH=11 bo'lgan ammiakli bufer aralashma va 1 % li erioxrom qora T indikatorining bir necha kristallari (odatda ~1 % li erioxrom qorasi osh tuzining mayda kristallari bilan aralashtirib tayyorlanadi) qo'shiladi. So'ngra hosil bo'lgan eritma standartlanadigan EDTA eritmasi bilan aralashmaning qizil rangi ko'kka kirgunga qadar titrlanadi. Oxirgi nuqtaga yaqin qolganda titrant juda sekinlik bilan tomchilatib qo'shilishi zarur. Titrlash kamida uch marta takrorlanadi va o'rtacha natija olinadi.

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