I bob. Asosiy kimyoviy tushuncha va qonunlar

Mavzu: Eruvchanlik koeffitsiyentiga doir masalalar.

Eruvchanlik koeffitsiyenti (S) bilan eritmaning massa ulushi (𝜔) orasida quyidagi bog’liqlik bor:

𝜔=

bu yerda S – moddaning eruvchanlik koeffitsiyenti [g].

Eruvchanlik koeffitsiyentiga doir masalalarni yechishda doim tegishli eruvchanlik koeffitsiyent qiymatini 100g suvga nisbatan olish kerak.

M1. (394) 30°C da KNO₃ ning 50g 20% li eritmasining to’yinishi uchun yana 6,8g KNO₃ qo’shilishi kerak. Shu tuzning eruvchanligini aniqlang.

m 50g =0,2 + =6,8 S-?

=50∙0,2=10g =10+6,8g=16,8g msuv =(50+6,8)-16,8=40g 16,8g KNO3 - 40g suv 42 = x -100g suv S30°C=42g

Agarturlitemperaturadagiaynituzningeruvchanlikkoeffitsentlariberilib, eritmasovutilgandaqanchacho’kmahosilbo’lishiso’ralsa, cho’kmamassasinihisoblashuchuneruvchanlikkoeffitsentlariayriladi.

M2. (228) Agarammoniyxloridning 10°Cdagito’yinganeritmasitarkibida 50 mlsuvbo’lsa, bueritma 0°Cgachasovutilgandaqanchaammoniyxloridcho’kmasitushadi (S_0°C=37,0gS_100°C=77,0g).

S0°C =37g S100°C =77g msuv=50g mcho’kma- ?

100g suv - 40g cho’kma 50g suv - x=20g cho’kma

M3. (229) AgNO₃ ning 60°C dagi to’yingan eritmasi 20°C gacha sovutilganda 15g tuz cho’kmaga tushishi uchun talab etiladigan tuz va suvning massasini toping.

S20°C =222g S60°C=450g 228g cho’kma mcho’kma=15g m(AgNO3)-? msuv-?

450g AgNO3 – 228g cho’kma x= 29,6g AgNO3 - 15g cho’kma 100g suv – 228g cho’kma y=6,6g suv – 15g cho’kma

M4. (223) 80°C da 300g to’yingan NaNO₃ eritmasi 20°C gacha sovutilganda cho’kmaga tushgan tuzning massasini va eritmada qolgan tuzning massa ulushini (%) aniqlang.

S20°C=88g S80°C=148g 60g cho’kma me =300g mcho’kma - ? 𝜔 - ?

248g eritma – 60g cho’kma 300g -x= 72,6g cho’kma

M5 (225) Bir tuzning xona temperaturasidagi to’yingan eritmasidagi massa ulushi 0,2 ga teng. Shu tuzning massa ulushi 0,3 bo’lgan 300g eritmasi xona temperaturasigacha sovutilganda , qancha (g) tuz cho’kmaga tushadi.

𝜔1=0,2=20% 𝜔2=0,3=30% me=300g mcho’kma-?

𝜔= 0,2= 0,85S1=20 S1=25g 0,3= 0,75S2=30 S2=42,9g 17,9 g cho’kma 142,9g eritma – 17,9g cho’kma 300g - x=37,5g cho’kma

M6. (401) CaBr₂ ning 80gto’yinganeritmasiga 20gsuvsiztuzsolinib, aralashmadagituzeribketgungaqadarqizdirildivaso’ngraboshlang’ichtemperaturagaqadarsovutildi. Bunda 41,32g kristallogidrat cho’kmaga tushdi. To’yingan eritmadagi suvsiz tuzning massa ulushi 58,7% ga teng. Kristallogidratformulasinitoping.

=58,7=0,587 + =20g CaBr2∙nH2O-?

m(CaBr2)=80∙0,587=46,96g mum(CaBr2)=66,96g (sovuq eritmada) m(CaBr2)=(100-41,52)∙0,587=34,33g mcho’kma(CaBr2)=66,96-34,33=32,63g msuv=mkrist – =41,32 – 32,63=8,89g 200g CaBr2 – x │x=54g n(H2O)= 32,63 – 8,89g suv CaBr2∙3H2O