AP Chemistrymediummcq1 pt
A mechanism consists of Step 1: A + B -> X; Step 2: X + C -> Y; Step 3: Y -> D. What is the overall reaction?
A.A + B + C -> D
B.A + B + C -> D + X + Y
C.A + B + X -> Y + D
D.A + B + 2C -> 2D
Explanation
Core Concept
Summing all elementary steps and canceling species that appear on both sides yields the net equation. X is produced in Step 1 and consumed in Step 2, and Y is produced in Step 2 and consumed in Step 3, so both intermediates cancel completely. Only A, B, and C remain as reactants and D as the product. Intermediates never appear in overall equations precisely because they are made and destroyed within the mechanism.
Correct Answer
AA + B + C -> D
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