Question

Compound A is white colour substance or powder taken in a test tube and add with solid
iodine to give yellow precipitate is compound B. write down its reaction and equations

Please help me
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Answer 1

Answer:

The chloride, bromide and iodide precipitates are shown in the photograph:

The chloride precipitate is easily identified, but the other two are quite similar to each other. They can only be differentiated in a side-by-side comparison. All the precipitates change color if they are exposed to light, taking on gray or purple tints. The absence of a precipitate with fluoride ions is unhelpful unless it is known that a halogen is present; otherwise, it indicates that there is no chloride, bromide, or iodide.

The chemistry of the test

The precipitates are insoluble silver halides: silver chloride, silver bromide or silver iodide. The formation of these is illustrated in the following equations:

Ag+aq+Cl−(aq)→AgCl(s)(1)

Ag+aq+Br−(aq)→AgBr(s)(2)

Ag+aq+I−(aq)→AgI(s)(3)

Silver fluoride is soluble, so no precipitate is formed.

Ag+aq+F−(aq)→Ag+aq+F−(aq)(4)

Confirming the precipitate using ammonia solution

Ammonia solution is added to the precipitates.