How can you distinguish chemically between the following pairs of substances in one or two steps.
a)HCl and H2SO4
b) KNO3 and K3PO4
a)
Add AgNO3, HCl forms white ppt of AgCl, soluble in NH3.
Add BaCl2, H2SO4 forms white ppt of BaSO4, not soluble in HNO3.
b)
Add AgNO3, K3PO4 forms yellow ppt of Ag3PO4. Soluble in HNO3.
To chemically distinguish between the following pairs of substances, HCl and H2SO4, and KNO3 and K3PO4, you can utilize some simple chemical reactions. Here is the step-by-step procedure for each pair:
a) HCl and H2SO4:
Step 1: Add a small amount of each substance separately to a test tube.
Step 2: To the first test tube containing HCl, add a few drops of silver nitrate (AgNO3) solution.
Observation: If a white precipitate forms, it indicates the presence of chloride ions (Cl-) in HCl. This reaction produces insoluble silver chloride (AgCl).
Step 3: To the second test tube containing H2SO4, add a few drops of barium chloride (BaCl2) solution.
Observation: If a white precipitate forms, it indicates the presence of sulfate ions (SO42-) in H2SO4. This reaction produces soluble barium sulfate (BaSO4).
b) KNO3 and K3PO4:
Step 1: Add a small amount of each substance separately to a test tube.
Step 2: To the first test tube containing KNO3, add a few drops of silver nitrate (AgNO3) solution.
Observation: If a white precipitate forms, it indicates the presence of nitrate ions (NO3-) in KNO3. This reaction produces insoluble silver nitrate (AgNO3).
Step 3: To the second test tube containing K3PO4, add a few drops of calcium chloride (CaCl2) solution.
Observation: If a white precipitate forms, it indicates the presence of phosphate ions (PO43-) in K3PO4. This reaction produces insoluble calcium phosphate (Ca3(PO4)2).
Note: It is important to perform these tests in a well-ventilated area or inside a fume hood, and always follow appropriate safety precautions. Additionally, these reactions are based on specific chemical properties of the given substances and might not be applicable in all scenarios.