Mavzu: modda va uning xossalari

Maqsad: o'quvchilarni eritmalardan erigan moddani ajratib olishga o'rgatish.
Jihozlar: shisha stakan (1), plastik taglik (2), keramik plita (3), quruq yoqilg'i (4), bug'latish kosachasi (5), 50 ml li polipropilen stakan (6), 150 ml li polipropilen stakan (7), plastmassa shpatel (8), shisha tayoqcha (9), laboratoriya shtativi (10), probirkalar va shtativ (11).
Reaktivlar: natriy xlorid (osh tuzi), distillangan suv.

Jihozlar to'plami Laboratoriya shtativi

Ishni bajarish tartibi:

1. 
   50 ml li polipropilen stakanga 2-3 plasmassa shpatelda osh tuzi solinadi.
   
2. 
   Osh tuzi solingan stakanga 30 ml suv quyiladi.
   
3. 
   Shisha tayoqchaning uchi bilan stakandagi tuzni erib ketgunicha suv bilan aralashtiriladi.
   

1. 
   Hosil bo'lgan eritmani bug'latish uchun stakandagi eritmadan bug'latish kosachasin-ing 1/2 qismigacha quyiladi.
   
2. 
   Ichida eritmasi bo'lgan bug'latish kosachasini temir shtativning halqasiga joylash-tiriladi.
   
3. 
   Quruq yoqilg'i keramik plita ustiga qo'vlib yoqiladi va kosachadagi eritmani osh tuzi kristallari hosil bo'lguniga qadar qizdiriladi.
   
4. 
   B ug'latish kosachasidagi eritmadan suv bug'lanib, kristallar hosil bo'lgach, kosacha xona haroratiga qadar sovutiladi.
   
5. 
   Sovugan bug'latish kosachasidagi osh tuzi kristallarining miqdori (shisha idishdagi tuz kristallari bilan solishtiriladi) shpatelda taqqoslanadi.
   

Nazorat uchun savollar:

1. 
   Toza moddalar va aralashmalarga misollar ayting.
   
2. 
   Aralashmalarni tozalashning qanday usullarini bilasiz?
   
3. 
   Osh tuzi suvda eritilganda qanday eritma hosil bo'ladi?
   

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