Transcript SATL-green chemistry-PART

Systemic Investigation of [AI+++]
SI - 8
Idea of the experiment:
(1)Qualitativeinvestigation of [Al+++] in a systemic
cycle.
(2) Preparation of different [Al+++] compounds.
(3) Inter-conversion of [Al+++] compounds.
Al+++
Chloride Salt
Exp. 1
Exp. 2
HCl
Exp. 3
Whit ppt.
Aluminum phosphate
Reagents Used:
(SI-8)
(1) Acid:
HCl: (1:1 solution).
(2) Alkali:
NaOH
White gelationus ppt.
Aluminum hydroxide
Coloreless
(3) Salts:
Sodium phosphate.
Aluminum chloride, (5 gm) of the solid dissolved
in (100 ml) of distilled water.
Exp. 1
Add (1 ml) of sodium hydroxide solution to ca. (2 ml)
of aluminum chloride solution.
What do you observe?
Observation:
White gelatinous ppt. of Al (OH)3.
Equation:
AlCl3  3NaOH Al(OH)3   3NaCl
Exp. 2
Dissolve the precipitate obtained from experiment
(1) in (2 ml) NaOH solution.
What do you observe?
Observation:
The precipitate dissolves in NaOH.
Equation:
Al(OH)3  NaOH Na AlO 2  H 2 O
Exp. 3
1- Add one ml of HCl to the solution produced from
exp. 2.
What do you observe?
Observation:
White ppt. of Al(OH)3.
Equation:
3NaAlO 2  6HCl  2AlOH3   3NaCl AlCl3
1- Dissolve the precipitate obtained in 0.5 ml of HCl
and then add few drops of sodium phosphate.
What do you observe?
Observation:
White ppt. of aluminum Phosphate.
Equation:
AlCl 3  Na 3PO4  Al PO4   3NaCl
Finally
Dissolving the Al PO4 precipitate in HCl,
gives the starting solution of AlCl3.
Systemic Investigation of [Fe+++]
SI - 9
Idea of the experiment:
(1)Qualitative investigationof [Fe+++] in a systemic
cycle.
(2) Preparation of different [Fe+++] compounds.
(3) Inter-conversion of [Fe+++] compounds.
Fe+++
HCl
Chloride salt
Exp.2
(Violet color)
Exp.1
(Reddish brown ppt.)
Iron (III) hydroxide
Iron salycilate complex
(SI - 9)
Reagents Used:
(1) Acid:
HCl: (1:1 solution).
Salicylic acid
(2) Alkali:
Sodium hydroxide
(3) Salts:
Ferric chloride, (5 gm) of the solid dissolved in
(100 ml) of distilled water.
Exp. 1
Add (1 ml) of sodium hydroxide solution to ca. (2 ml)
of Iron (III) solution.
What do you observe?
Observation:
Reddish brown ppt. of iron (III) hydroxide.
Equation:
FeCl3  3NaOH FeOH3   3NaCl
Exp. 2
Dissolve the precipitate from experiment (1) in (1
ml) dil HCl and then add few drops of salicylic acid.
What do you observe?
Observation:
Violet colour of iron salicylate complex.
Finally
Dissolving iron salicylate complex in HCl,
gives the starting solution of FeCl3.
IF EXP. (II) GIVES NO
PRECIPITATE THEN CARRY
OUT EXP. IV
EXPERIMENT. IV
To (1 ml) of the unknown solution, add (2ml) of
ammonium chloride and (1 ml) of ammonium
hydroxide and (1 ml) of sodium sulphide solution.
What do you observe?
Observation:
If black ppt.
If buff ppt.
If white gelatinous
ppt.
This means that (Ni2+)
This means that
This means that
or (Co2+) may be present (Mn2+) is present .
(Zn2+) is present .
Investigate the cation by Carry out (SI- 12) to Carry out (SI- 13) to
using (SI - 10) or (SI- 11) confirm this result. confirm this result.
Systemic Investigation of [Ni2+]
(SI - 10)
Idea of experiment:
(1)Qualitative investigation of [Ni2+] in a systemic
cycle.
(2) Preparation of different [Ni2+] compounds.
(3) Inter-conversion of [Ni2+] compounds.
Ni2+
HCl
Chloride Salt
Red ppt.
Ni (DMG)2
Exp.4
Exp.1
Green ppt.
Ni (OH)2
(SI - 10)
Reagents Used:
- Nickel chloride
- Dimethylglyoxime.
- Sodium hydroxide.
- Ammonium Hydroxide.
- Hydrochloric acid.
Green ppt.
Ni (OH)2
Exp.2
Blue solution.
[Ni (NH3)4]2+
Exp.3
Exp. 1
Add (1/2 ml) of NH4OH very dilute solution to ca.
(2ml) of nickel chloride solution.
What do you observe?
Observation:
Green ppt. of nickel hydroxide.
Equation:
NiCl2  2 NH4 OH  Ni(OH)2   2NH4 Cl
Exp. 2
Dissolve the precipitate obtained from exp.1 in
excess NH4OH ca. (2ml).
What do you observe?
Observation:
Blue solution of [Ni(NH3)4]2+ complex.
Exp. 3
Add (1 ml) of NaOH to the solution produced from
exp. 2.
What do you observe?
Observation:
Green ppt. of Ni(OH)2.
Exp.4
Add (1 ml) of NH4Cl to the precipitate obtained
from exp. 3. to dissolve the ppt. Then, add ca. (1/2
ml) of dimethylglyoxime.
What do you observe?
Observation:
Red ppt. of nickel dimethylglyoxime complex.
Finally
Addition of (1-2 ml) of HCl to the complex
obtained from exp. 4 gives the starting
NiCl2 solution.
Systemic Investigation of [CO2+]
(SI - 11)
Idea of the experiment:
(1)Qualitativeinvestigation of [CO2+] in a systemic
cycle.
(2) Preparation of different [CO2+] compounds.
(3) Inter-conversion of [CO2+] compounds.
CoCl2
HCl
Chloride Salt
Pink solution Cobalt
amine complex
Exp.3
Blue ppt.
Basic cobalt salt
(SI - 11)
Reagents Used:
- HCl (1:1 Solution).
- HNO3 (1:1 Solution).
- Cobalt (II) Chloride.
- Sodium Hydroxide.
- Ammonium Hydroxide.
Exp.1
Blue ppt.
Co (OH)2
Exp.2
Exp. 1
Add ca. (1/2 ml) of NH4OH solution to ca. (2 ml) of
CoCl2 solution.
What do you observe?
Observation:
Blue ppt of Co(OH)2.
Equation:
CoCl2  2NH4 OH 
 Co(OH)2   2NH4 Cl
Exp. 2
Dissolve the precipitate from experiment (1) in (2
ml) NH4OH, and then add (1 ml) of NaOH.
What do you observe?
Observation:
Blue ppt of basic cobalt salt.
Exp. 3
Heat the precipitate obtained from exp. 2.
What do you observe?
4Co OH  Cl  8NH 3  6H 2 O  O 2 
 4Co(NH 3 )(OH) 3  4NH 4 Cl
Observation:
Pink solution of cobalt - amine complex.
Finally
Addition of HCl to the solution obtained
from exp. 3, gives the starting CoCl2
solution.
Systemic Investigation of [Mn2+]
(SI - 12)
Idea of the experiment:
(1)Qualitative investigationof [Mn2+] in a systemic
cycle.
(2) Preparation of different [Mn2+] compounds.
(3) Inter-conversion of [Mn2+] compounds.
Mn2+
HCl
Chloride salt
Exp.2
Buff ppt.
MnS
Exp.1
Buff ppt.
Mn (OH)2
(SI - 12)
Reagents Used:
- Manganese chloride.
- HCl, (1:1 Solution).
- Ammonium Chloride.
- Ammonium Hydroxide.
- Sodium sulphide.
Exp. 1
Add (1 ml) of ammonium hydroxide to ca. (2 ml) of
manganese chloride solution.
What do you observe?
Observation:
Buff ppt. of Mn(OH)2
Equation:
MnCl2  2NH4OH Mn(OH)2   2 NH4Cl
Exp. 2
Add ca. (2 ml) of ammonium chloride to the
precipitate obtained from exp. 1 and then add (1 ml)
of sodium sulphide.
What do you observe?
Observation:
Buff ppt of MnS.
Equation:
MnCl2  Na 2S 
 MnS  2 NaCl
Finally
dissolving the precipitate obtained from
exp. 2 in conc. HCl, gives the starting
solution of MnCl2