- Oxi hoa hau het kim loai va phi kim 6 nhiet do
6.31. 1 So dd thilt bi dilu che hidro :
3
2. Dung d'ng dong cd dung tich 100 cm .
3. Cdt nhiing la kem nhd cd dien tieh (kfch thudc) bdng nhau tft mdt la kem. 4. So sanh kit qua :
a) Khf dugc giai phdng d thf nghiem 1 nhanh han thf nghiem 3, vi dien tfch tiep xuc cfta Zn vdi HCI d thi nghidm 1 ldn ban, trong khi dd nhiet do cua dung dich H2SO4 la nhu nhau.
b) Khf hidro duge giai phdng d thf nghidm 3 nhanh ban thi nghiem 2, vi nhiet do cua dung dich H2SO4 d thf nghiem 3 cao ban, trong khi dd dien tfch tie'p xuc giua kem va axit la nhu nhau.
5. Dd thi bilu diln cdc phan ftng :
Dudng cong c bilu thi cho thi nghiem 1, phan ftng xay ra la nhanh nhdt, ftng vdi dudng cong cd dd ddc ldn nhd't.
Dudng cong b bieu thj cho thf nghiem 3, phan ftng xay ra trung binh, ftng vdi dudng cong cd do ddc trung binh.
Dudng cong a bieu thi cho thf nghiem 2, phan ftng xay ra chdm nhd't, ftng vdi dudng cong cd dd ddc nhd nhd't.
6. Sau cac thi nghiem tren, kem cdn du. Nhu vdy thi tfch khf H2 thu dugc phu thudc vao lugng H2SO4 tham gia phan ftng :
2 x 5 0 _ . ^ ,^ nH2 =nH2S04 = 1 0 0 0 " = ^'^^""°^^ '
Thi tich khf H2 thu dugc trong dilu kien thf nghiem : VH^ = 24 X 0,1 = 2,4 (/) hodc 2400 em^
Ta ghi sd 2400 (cm ) tren true y, nai giao diem gifia true y va dudng ndm ngang keo dai cua 3 dudng cong.
6.32. Hudng ddn : cd thi la nhung phan ftng hoa hgc sau :
Dung mdt sd kim loai, phi kim khft H2SO4 thanh SO2 thf du : H2SO4 ddc + Cu
H2SO4 ddc + S H2SO4 ddc + C vv...
Dung khf oxi dl oxi boa H2S hodc mudi sunfua thanh SO2 thf du : H2S + O2
FeS2 + O2
V.V....