- Oxi hoa hau het kim loai va phi kim 6 nhiet do
6.35.1 a) Mg; b) CUCO3 ; c) CUCO 3, CuO ;
d) Fe203 , Fe(0H)3 ; d) Mg, AI2O3. 2. Cu
6.36. a) Nhiing thf nghiem chftng minh dung dich H2SO4 loang cd tfnh chdt chung cua axit :
- Tdc dung vdi oxit baza : MgO
- Tac dung vdi baza (phan ftng trung boa): NaOH - Tac dung vdi mudi : CUCO3
- Tac dung vdi kim loai boat ddng : Fe (HS tu vie't cac phuang trinh hod hgc)
b) Nhftng thf nghiem chftng minh H2SO4 ddc cd tfnh chdt hod hgc ddc trung : - Tinh chat oxi hod manh : Tac dung vdi Cu.
- Tfnh chd't hao nudc : Tac dung vdi CUSO4.5H2O CUSO4.5H2O +H2S04«^) > Q1SO4 + 5H2O
(Chat rdn, mau xanh) (Chai ran, mau trang) 6.37. Cac phuang trinh hod hgc :
a) Axit sunfuric tac dung vdi CuO :
H2SO4 + CuO -> CUSO4 + H2O (1) b) Axit sunfuric tdc dung vdi Cu :
2H2S04(d) + Cu ^ CUSO4 + SO2 + 2H2O (2)
Gia sft mudn cd n mol CUSO4, theo (1) cdn n mol H2SO4, theo (2) cdn 2n mol H2SO4. Nhu vdy, dung H2SO4 tac dung vdi Cu se tdn mdt lugng axit nhilu ban gap 2 ldn vi : Trong 2n mol H2SO4 tham gia phan ftng, chi ed n mol H2SO4 tao mudi CUSO4 va n mol H2SO4 eon lai bi khft thdnh n mol S02- 6.38. De dilu che SO2 dugc thudn Igi, ta chgn cac mudi Na2S03 va CUSO3 tdc dung vdi dung dich H2SO4. Vi nhiing chd't nay tac dung vdi nhau dl dang, tao ra cac mudi tan trong nudc (Na2S04 vd CUSO4) (HS tg vidt cac phuang trinh hod hgc).
Cac mudi CaS03, BaS03 d giai doan ddu cd tac dung vdi H2SO4 giai phdng khf SO2. Nhung sau dd phan ftng se diing lai vi tao ra mudi khdng tan la CaS04, BaS04. Nhftng mudi nay ngdn can sg tiep xuc gifta axit va mudi sunfit.
6.39. Chd't rdn A : Natri clorua (NaCl). Chdt khf B : Hidro clorua (HCI). Chd't khf C : Clo (CI2). 6.40. C. 6.41. a) Xem dd thi: m(g) 40 50 60 80 100 t(°C) Hinh 6.15
b) Dd tan cfta cdc mudi KCIO3 va NaCl tdng theo nhiet dd. Trong dd, dd tan cua KCIO3 tdng nhanh, dd tan cfta NaCl tdng chdm khi nhiet dd tdng. Dd tan cfta mudi Na2S04 tdng khi nhiet dd tdng din 50°C. Sau dd dd tan cfta Na2S04 lai bi giam khi nhiet dd tang tft 50°C ddn 100°C.
Chdt cd dd tan ldn nhdt la Ka03, d nhiet do 100°C cd dd tan la 52 g/100 g H2O. c) Chd't cd dd tan ldn nhd't : d 30°C la Na2S04 cd S ~ 36 g/100 g H2O ; d 90°C la KCIO3 cd S =i 44 g/100 g H2O.
6.42. B. 6.43. B. 6.43. B. 6.44. B. 6.45. D.
Bai 46
LUYEN TAP CHLTONG 6
6.46. Cac khf sinh ra :
a) 1. Cacbon dioxit (CO2) ; 2. Clo (CI2) ; 3. Hidro (H2) ; 4. Luu huynh dioxit (SO2) ; 5. Luu huynh dioxit (SO2); 6. Oxi (O2).
b) Cdch nhdn biet cac khi:
1 Khf lam mat mau dung dich KMn04 la SO2. Khi lam vdn due dung dich Ca(0H)2 la CO2. Khi chdy trong khdng khf vdi tilng nd nhd la H2. Khi lam than hdng bung chdy la O2.
Khf lam mdt mau gidy quy tfm dm la CI2. 6.47. Thft tg diln cdc chu :
xanh, trdng, tach nudc, hdo nudc. hidro clorua, axit manh, khdng bay hoi. khdng (0) ; +2, +4, +4 ; oxi hod manh. (HS tu vie't cac phuang trinh hod hgc).
6.48. Hudng ddn : ten cdc dung dich
a) A : Dung dich H2SO4; B : Dung dich NaOH ; C : H2O ; D : Dung dich HQ. b) E : Dung dich Na2S04 ; F : Dung dich AICI3 ; G : Dung dich MgClj ; H : Dung dich MgS04.
6.49. a) Axit vfta cd tinh khft vfta cd tfnh oxi hod : H2SO3
H2SO3 cd tfnh khft khi tdc dung vdi chdt oxi hod manh, thf du :
+4 0 +6 -1
H2SO3 + CI2 + H2O -^ H2SO4 + 2HC1
H2SO3 cd tfnh oxi hoa khi tdc dung vdi chd't khft manh, thi du :
44 - 2 0
H2SO3 + 2H2S ^ 3S(r) + 3H2O