Question

Can someone please give me the chemical equation and directions on how to test for each individual solution below and how to tell if my solution has one of each category? So a test for HCl and HNO3 excetera.?

Acid-HCl,HNO3,H2SO4

Base-NaOH, NH3, Na2S

Chloride Salt-NaCl,BaCl2,CuCl2

Nitrate salt-AgNO3,Cu(NO3)2, Fe(NO3)3

Sodium Salt-NaI,Na2SO4,Na2CO3

Answer 1

Qualitative tests

A) Acids : HCl, HNO3, H2SO4

Add AgNO3 to the three test tubes with one acid in each.

No ppt : HNO3 present

ppt : HCl or H2SO4

AgNO3 + HCl = AgCl(ppt) + HNO3

2AgNO3 + H2SO4 = Ag2SO4(ppt) + 2HNO3

Add BaCl2 to the test tube containing HCl and H2SO4

No ppt : HCl

ppt : H2SO4

BaCl2 + H2SO4 = BaSO4(ppt) + 2HCl

B) Base : NaOH, NH3, Na2S

Add Pb2+ solution to the three test tubes.

ppt forms and then dissolves again in solution : NaOH

Pb2+ + NaOH = Pb(OH)2(ppt) + OH- = Pb(OH)3-(soluble)

black ppt : Na2S

Pb2+ + Na2S = PbS(ppt) + 2Na+

No ppt : NH3

Add Cd2+ solution : ppt forms and then redissolves : NH3

C) Chloride salts NaCl, BaCl2, CuCl2

Add CrO4^2- solution to the three test tubes

no ppt : NaCl

2NaCl + K2CrO4 = Na2CrO4 + 2KCl

white ppt : BaCl2

BaCl2 + K2CrO4 = BaCrO4(ppt) + 2KCl

light blue ppt : CuCl2

CuCl2 + K2CrO4 = CuCrO4(ppt) + 2KCl

D) Nitrate salts AgNO3, Cu(NO3)2, Fe(NO3)3

Add HCl : ppt confirms AgNO3

AgNO3 + HCl = AgCl(ppt) + HNO3

Add KSCN : deep red coloration ppt : Fe(NO3)3

Fe3+ + SCN- = Fe(SCN)^3+(ppt)

Remaining would be Cu(NO3)2

E) Sodium salt NaI, Na2SO4, Na2CO3

Add acid then AgNO3 : ppt formed confirms NaI

AgNO3 + NaI = AgI(ppt) + NaNO3

Add acid then BaCl2 : ppt confirms Na2SO4

Na2SO4 + BaCl2 = BaSO4(ppt) + 2NaCl

Add HCl : CO2 gas evolved confirms Na2CO3

Na2CO3 + 2HCl = 2NaCl + CO2 + H2O