| EXPERIMENT | OBSERVATIONS | INFERENCE |
| 1.PHYSICAL EXAMINATION: a) Colour of the given salt. b) Noted the smell of the salt. | White No specific odour | Cu2+, Mn2+, Co2+, Ni2+, Fe3+, absent. NH4+, S2- and CH3COO- may be absent. |
| 2.DIL. SULPHURIC ACID TEST Treated a pinch of salt with dil. H2SO4 and warmed. | No gas evolved. | CO32-, S2-, SO32-, NO2-, may be absent. |
| 3.CONC. SULPHURIC ACIS TEST Heated a pinch of the salt with conc. Sulphuric acid and added to it a paper pellet. | colourless gas with pungent smell | Cl- may be present. |
| 4.CONFIRMATORY TEST a) Silver nitrate test. Sodium carbonate extract + dil. HNO3 + AgNO3 solution b) Chromyl chloride test:- (i)Mixture + conc. H2SO4 + solid K2Cr2O7 + heat (ii)The gas which is evolved is passed in NaOH solution (iii)To above solution add AcH + PbAc2 | White ppt. is formed which is soluble in excess of NH4OH Dark reddish brown gas is evolved Solution of NaOH is change to yellow colour Yellow ppt is obtained | Cl- confirmed. Cl- confirmed. |
| 5.HEATED A PINCH OF SALT WITH CONC. NaOH SOLUTION | No ammonia gas evolved. | NH4+ absent. |
| 6.TO A PART OF THE O.S. ADDED 1-2 mL OF Dil. HCl | No ppt. formed. | Group I absent. (Pb2+ absent) |
| 7.TROUGH A PART OF THE ABOVE SOLUTION, PASSED H2S GAS | No ppt. formed. | Group II absent (Pb2+, Cu2+, As3+ absent) |
| 8. TO THE REMAINING SOLUTION, ADDED A PINCH OF NH4Cl. BOILED THE SOLUTION, COOLED IT AND ADDED EXCESS OF NH4OH SOLUTION. | No ppt. formed. | Fe3+, Al3+, absent. |
| 9.THROUGH A PART OF THE ABOVE SOLUTION, PASSED H2S GAS | No ppt. formed. | Group IV absent. (Zn2+, Mn2+, Co2+ and Ni2+absent) |
| 10. TO THE REMAINING AMMONICAL SOLUTION ADDED (NH4)2CO3 SOLUTION. | White ppt. formed. | Group V present. (Ca2+, Ba2+, Sr2+ may be present) |
| 11. CONFORMATORY TEST Filtered the above white ppt. dissolved the ppt. in hot dilute acetic acid and divide into three parts a) 1st part + K2Cr2O7 b) 2nd part + (NH4)2SO4 c) 3rd par + (NH4)2C2O4 Flame test Dipped the Pt wire in dil. HCl + touch the ppt and ignite it | Yellow ppt. is not formed. White ppt. is not formed White ppt is formed Red flame like brick is produced | Ba2+ absent. Sr2+ absent. Ca2+ present Ca2+ is confirmed. |
RESULT: ACID RADICAL: Cl- BASIC RADICAL: Ca2+
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