AP Chemistrymediummcq1 pt
For a weak acid, which approximation allows skipping the quadratic?
A.x is negligible compared with the initial concentration
B.x equals [HA]₀
C.Ka equals zero
D.[H⁺] equals [HA]₀
Explanation
Core Concept
When Ka is small enough that x < 5% of [HA]₀, the denominator simplifies to [HA]₀. The result is checked afterward; if the check fails, the quadratic is required.
Correct Answer
Ax is negligible compared with the initial concentration
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