1. by Admin PH Mohamed Hamdy
I am proud to be
pharmacist

2. Analytical chemistry lecture (2) lecturer:Dr.Magda

3. Hello everybody let’s start but at first there is summary for lecture (1) ↓↓

4. Test CO3ˉ ˉ HCO3ˉ Dry Reactions Solid+dil.Hcl Then warm
eff with evolution of colorless gas (CO2↑), which cause turbidity to limewater and disappear after prolonged time
Wet Reactions
(1)AgNo3
White ppt og Ag2No3
-soluble in HNo3,Amonia
-Turn Brown if boiled
No PPt on cold ↓∆
Give ppt
(2) Bacl2
Cacl2
MgSo4
White ppt of Baco3
White ppt of Caco3
White ppt of MgCo3
- sol. In mineral acids

5. Some notes - Dr. Magda canceled spot test -
Some notes - Dr.Magda canceled spot test -*(star) means positivecharge (+) in the slides 

6. Sulphur containing Anions:- 1-Sulphur Sˉˉ 2-Sulphide SO3ˉˉ 3-Thiosulphate S2o3ˉˉ 4-Sulphate SO4ˉˉ 5-persulphate S2O8ˉˉ

7. sˉˉ,SO3ˉˉ,S2O3ˉˉ are reducing agents can react with oxidizing agents like →K2Cr2O7 pot.di chromate → KMno4 pot.permenganate

8. (1) Sulphide Sˉˉ :- - Parent Acid:- H2S (weak acid) H2S ↔ H
(1) Sulphide Sˉˉ :- - Parent Acid:- H2S (weak acid) H2S ↔ H* + HS ˉ ( hydro sulphide) HS ˉ↔ H*+ Sˉ(Sulphide )

9. Dry Test :- (Actions of Dil. Hcl ) -Sˉˉ + 2H
Dry Test :- (Actions of Dil.Hcl ) -Sˉˉ + 2H*→H2S gas ↑↑ or Na2S + 2HCl → H2S ↑↑ + 2 NaCl H2S can be Detected by :- 1-gas with offensive rotton egg odour رائحة البيض الفاسد  2-It can Blacken filter paper moisted with leadacetate Pb(Ac)2

10. Pb(Ac)2 + H2S → PbS ↓↓ Black ppt Pb
Pb(Ac)2 + H2S → PbS ↓↓ Black ppt Pb** + H2S →PbS ↓↓Black ppt Wet Reactions : - - Reactions with BaCl2:- ( - ve ) -Reactions with AgNO3(Silvernitrate): Sˉˉ + 2Ag* → Ag2S ↓↓ Black ppt which is soluble in Dil.HNO3 , Insoluble in Ammonia and KcN

11. -Reactions with Pb(Ac)2 :- Sˉˉ + Pb
-Reactions with Pb(Ac)2 :- Sˉˉ + Pb** → PbS ↓↓ Black ppt -Reactions with FeCl3:- 3Sˉˉ + 2F*** → Fe2S3 ↓↓Black ppt ( Soluble in dil.Acids like dil.HCl)

12. (2) Sulphite SO3ˉˉ :- - Parent Acid :- H2SO3 Sulphurous Acid weak acid ( easily decomposed) - Dry Test :- SO3ˉˉ+ 2H* →H2SO3→H2O+SO2↑ SO2 Can be detected by the following :- 1- It has Burnt Sulphur odour 2- cause Turbidity to limewater SO2 + Ca(OH)2→CaSO3↓↓+ XSS SO2 → Ca(HSO3)2 (soluble )

13. Note : Sulphite Has Reducing properties Cr2O7ˉˉ + 2 H
Note : Sulphite Has Reducing properties Cr2O7ˉˉ + 2 H* + SO2 → SO4ˉˉ + 2Cr*** (green colour )+ H2O

14. (-)Wet Reactions :- -Reaction with BaCl2 :- SO3ˉˉ + Ba
(-)Wet Reactions :- -Reaction with BaCl2 :- SO3ˉˉ + Ba** →BaSO3 ↓↓( white ppt sol. In dil HCl ) BaSO3 + [O]→ BaSO4↓↓(white ppt which is insol. In dil HCl ) - Reaction with AgNO3 :- 2Ag* + SO3ˉˉ → Ag2SO3↓↓ ( white ppt ) Ag2SO3 (Δ)→2Ag˚↓↓ +Ag2SO4+SO2↑ ( Grey or black ppt )

15. Note : Silver sulphite Is soluble in HNO3, Ammonia but excess sulphite give acomplex whichon boiling give grey ppt of mettalic Ag˚ Ag2SO3 + SO3 (xss) →2[Ag(SO3)2]ˉˉˉ(boiling)→2Ag˚↓+ Ag2SO4 + SO2 ↑ (grey or black ppt )

16. -Reaction with Pb(AC)2:- Pb
-Reaction with Pb(AC)2:- Pb** + SO3ˉˉ →PbSO3↓↓ + [O] →PbSO4 ↓↓ ( PbSO3 is white ppt which is soluble in cold HNO3 and on boiling oxidised to PbSO4 )

17. -Reaction with FeCl3 :- 2Fe
-Reaction with FeCl3 :- 2Fe** + 3SO3ˉˉ → Fe(SO3) (Red complex) Fe(SO3)2(Δ)→Reddish Brown ppt of Basic iron salt

18. System of exam questions (1)- By equation only : what is the effect of silver nitrate or FeCl3 on ( Sˉˉ , SO3ˉˉ,S2O3ˉˉ, SO4ˉˉ ) (2)- Write By equation the effect of HCl on ( Sˉˉ,SO3ˉˉ,S2O3ˉˉ, SO4ˉˉ)

19. As you see it is big lecture this is nearly half of it I hope it can be useful for you so at last thanks for god God willing,the second half will be soon PH Mohamed Hamdy