Kolloid eritmalarning olinishi

d. Kumush yodid zolining olinishi

( almashinish reaksiyasi)

Kumush yodid hosil bo’lish reaksiyasi quyidagi tenglama bilan ifoda etiladi:

AgI suvda yomon eriydi.

Kolloid zarrachalarining zaryadi kolloid hosil bo’lish oldida eritmada ortiqcha bo’lgan ion zaryadi bilan belgilanadi. Shuning uchun AgI zolining zarrachalari har xil ishorali zaryad bilan olinishi mumkin. Masalan eritmada KI ga qaraganda AgNO₃ ko’p bo’lsa, hosil bo’layotgan AgI kolloid zarrachalari musbat zaryadli bo’lib qoladi, chunki zarrachalar sirtida, asosan, Ag⁺ ionlari adsorbilanadi; xuddi shunga o’xshash agar eritmada AgNO₃ ga nisbatan KI ko’p bo’lsa, manfiy zaryadli kolloid zarrachalar olish mumkin.

Agar eritmada AgNO₃ ortiqcha bo’lsa, ko’p miqdor AgI molekulalaridan tashkil topgan zarracha yadrosi Ag⁺ ionlarini adsorbilaydi.