Chem Pracs

Lead doesn’t dissolve

Ammonia stinks

Strontium red flame

[[==CATION==[[

1. ^^Strontium^^

Prepare mixture of salt + Acetic acid

to this mixture add (NH4)2SO4 you get white ppt

2. ^^Alluminium^^

A=OS+ Nh4Cl+NH4Oh and dissolve in dil HCl

using A or Os add NaOH -→ you get gelatinous white mixture

use A and add blue litmus ---→ A blue jelly like substance

3. ^^Zinc^^

A= OS+NH4Cl+NH4OH+H2S

A+NaOH--→ white ppt (might be zinc)

A+K4[Fe(CN)6] -----→ Greenish white ppt

4. ^^Ammonium^^

a) Salt + NaOH and heat…. Bring rod dipped in HCl to the mouth of test tube ---→ pungent smell

NH4+NaOH→ Nh3+H2O+Na+

b)OS+NaOH+ Nessler’s reagent -----→ Reddish brown ppt

5. ^^Lead^^

A=Salt+ dil hcl

a) A+ K2CrO4---→ yellow ppt

b) A+ KI--→ golden spangles

Pb2+ + 2KI--→ PbI2 + 2K+

[[Anion[[

1. ^^Carbonate^^

Salt+ dil HCl (effervescence is noted (CO2 gas) which passed through Lime water turns milky

(cation)CO3+ 2HCl(aq)→(cation)Cl2+ CO2 + H20

2. ^^Chloride^^

a) $(Salt+water) or ( Salt+ Soda extract +HNO3)$ + AgNO3--→ Curdy white

AgNO3+MCL--→MNO3+AgCl

AgCl+NH4OH-→ Ag{(NH3)2]Cl+2H2O

b) Salt+K2Cr2O7+conc H2SO4----(heat)--→ red vapours

Red Vapour+ NaOh---→ yellow solution

Yellow solution +acetic acid + lead acetate ---→ yellow precipitate

c) Salt + conc H2S04--→ Frothing of colorless gas , when glass rod dipped in NH4OH is brought causes dense white fumes

3. ^^Nitrate^^

a) Salt+conc H2SO4 +paper pellets----→ Brown fumes turning FeSO4 solution black

MNO3+H2SO4-→MHSO4+HNO3

4HNO3+C--→ 2H20+4NO2+CO2

b) $WE or SE$ + FeSO4 +%%conc H2SO4(along the side)%%---→ brown ring is formed

4. ^^Sulphate^^

a) WE or SE+ BaCl2--→ White ppt insoluble in Conc HCl

MSO4+BaCl2--→ MCl2+BaSO4

b)$WE or SE$+CH3COOH+(CH3COO)2Pb--→ white ppt

5. ^^Phosphate^^

   a)WE or SE+ conc HNO3 (boil)+ (NH4)2MoO4----→ canary yellow ppt

   b) WE or SE +dil HCl (boil) + Magnesia mixture ----→ white ppt

   M2HPO4+MgCl2+NH4OH→ MgNH4PO4+2MCl+H2O