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JEE Advanced levelOne or more correct optionsDifficulty 3 of 3mc200

For $A + 2 B C$ , a student mixes $0.50 mol$ of A with $0.80 mol$ of B and isolates $0.30 mol$ of C. Select the correct statement(s).

AAfter the theoretical reaction is complete, $0.20 mol$ of A remains.
BB is the limiting reagent.
CThe percentage yield of C is $75%$ .
DThe theoretical yield of C is $0.40 mol$ .

Answer: B, C, D

A needs 2 x 0.50 = 1.00 mol B but only 0.80 mol B is present, so B limits. Theoretical C = 0.80/2 = 0.40 mol, and yield = 0.30/0.40 = 75%. At theoretical completion A used = 0.40 mol, so A left = 0.50 - 0.40 = 0.10 mol, not 0.20 mol.

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