25- lab mashg’uloti. 12-guruh elementlari. Rux, kadmiy va simob birikmalari. Laboratoriya ishining maqsadi

5- tajriba. Rux va kadmiy ammiakli kompleks birikmalarining olinishi
Ikkita probirka olib, birinchisiga rux sulfat eritmasidan 5-6 tomchi, ikkinchisiga kadmiy sulfat eritmasidan shuncha solib, cho‘kma hosil bo‘lguncha suyultirilgan NH₄OH eritmasidan qo‘shing (cho‘kma erib ketmasin) . Reaksiya tenglamalarini molekulyar va ionli shaklda yozing. Hosil qilingan cho‘kmalar to‘liq erib ketguncha yana NH₄OH eritmasidan qo‘shing. Hosil bo‘lgan kompleks birikmalarda rux va kadmiy ionlarining
koordinatsion soni 4 ga teng ekanligini hisobga olib, reaksiya tenglamalarini yozing.
___________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ Xulosa._______________________________________________________________________________________________________________________________________________________________________________________________________________Simob. Metall holidagi simob bug‘i va uning birikmalari zaharlidir. Shuning uchun mashg‘ulot vaqtida qo‘llanilgan idishlar ish tugallanishi bilan darhol laborantga topshirilib, qo‘llarni toza suvda sovun bilan yuviladi. Metall simob qo‘llaniladigan har bir tajriba maxsus taglik qo‘yilgan joyda o‘tkaziladi. Biror sabab bilan simob to‘kilsa, uning hamma tomcxilarini darhol yig‘ib, iflos simob yig‘iladigan shisha idishga solish kerak.
6-tajriba. Amalgama olish
a) natriy amalgamasi. Quruq farfor hovonchaga hushyorlik bilan 4-5 tomchi simob metallidan tomizing. Uning ustiga toza filtr qog‘ozida yangi kesilib quritilgan, moshdek 2-3 dona natriy metallidan qo‘shib, hovoncha dastasi bilan aralashtiring. Shunda
qattiq, shartli ravishda formulasi NaHg deb qabul qilingan natriy amalgamasi hosil bo‘ladi.
_______________________________________________________________________b) ammoniy amalgamasi. a) bandidagi tajriba davomida olingan natriy amalgamasining bir bo‘lagini probirkaga solib, uning ustiga ammoniy xloridning to‘yingan eritmasidan quying va tajribaning borishini kuzating. Ammoniy amalgamasi hosil bo‘ladi. U parchalanganda gaz ajralib (ammiak va vodorod) hajmi kattalashib, g‘ovak va uvalanib ketadigan bo‘lib qoladi. Amalgama parchalanib bo‘lgandan so‘ng probirkada simob
qoladi. Ammoniy amalgamasining olinish va parchalanish reaksiyalarini yozing.
_____________________________________________________________________________________________________________________________________________________________________________________________________________________ Xulosa._______________________________________________________________________________________________________________________________________________________________________________________________________________7-tajriba. Simob (I) va (II) oksidlarining olinishi.
Ikkita probirka olib, birinchisiga simob (I) nitrat eritmasidan 4-5 tomchi, ikkinchisiga simob (II) nitrat eritmasidan shuncha tomizib, har biriga alohida o‘yuvchi natriy
eritmasidan tomcxilab, cho‘kma hosil bo‘lguncha tomizing. Hosil bo‘lgan cho‘kmaning rangiga e’tibor berib, reaksiya tenglamasini molekulyar va ionli shaklda yozing.
___________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ Xulosa._______________________________________________________________________________________________________________________________________________________________________________________________________________