To distinguish NH4Br and NH4I from H2CrO4/Benzene, H2SO3/CCl4, and H3PO4/CHCl3, you can utilize the solubility differences of these compounds in certain solvents. Here's a breakdown:
NH4Br and NH4I: Both NH4Br and NH4I are ammonium salts. To distinguish them from the other compounds, you can use water as a solvent. Both NH4Br and NH4I are highly soluble in water, whereas H2CrO4, H2SO3, and H3PO4 are either insoluble or have very limited solubility in water. So, by dissolving the mixture in water, NH4Br and NH4I will readily dissolve, while the other compounds will remain as solids or precipitates.
H2CrO4/Benzene: H2CrO4 is chromic acid, which is not soluble in benzene. However, benzene is not a suitable solvent to distinguish H2CrO4 from the ammonium salts (NH4Br and NH4I) mentioned earlier, as they are all relatively soluble in organic solvents like benzene. Water is a better choice for the ammonium salts.
H2SO3/CCl4: H2SO3 is sulfurous acid, and it is not soluble in carbon tetrachloride (CCl4). To distinguish H2SO3 from the other compounds, you can use CCl4 as a solvent. H2SO3 will remain as a solid or undissolved, while the other compounds (NH4Br, NH4I, and H2CrO4) may dissolve or form a solution in CCl4.
H3PO4/CHCl3: H3PO4 is phosphoric acid, and it is not soluble in chloroform (CHCl3). Using CHCl3 as a solvent can help distinguish H3PO4 from the other compounds. H3PO4 will remain as a solid or undissolved, while NH4Br, NH4I, and H2CrO4 may dissolve or form a solution in CHCl3.
In summary, water can be used to distinguish NH4Br and NH4I from the other compounds, CCl4 can be used to distinguish H2SO3, and CHCl3 can be used to distinguish H3PO4.