AP Chemistryeasymcq1 pt
For A ⇌ B, K = 1000. A flask starts with 1.0 M A and no B. Approximately what is [B] once equilibrium is reached?
A.about 0.50 M
B.about 0.001 M
C.about 1.0 M
D.It cannot be estimated from K alone
Explanation
Core Concept
Let x be the amount converted, giving K = x/(1.0 - x) = 1000. A ratio this large forces the denominator to stay near 0.001, meaning almost all of A converts. Solving puts [B] near 0.999 M, essentially the full 1.0 M. Large K values drive reactions nearly to completion even though a trace of reactant always remains at equilibrium.
Correct Answer
Cabout 1.0 M
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