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Why is it that when you have a strong acid and weak base your equivalence point is less than 7

User Shawyeok
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1 Answer

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Step-by-step explanation:

When a strong acid, say
HCl reacts which a weak base, say
NH_3, the reaction is shown below as:-


\text{NH}_3 (\text{aq}) + \text{HCl} (\text{aq}) \rightarrow {\text{NH}_4^+}(\text{aq}) + \text{Cl}^-(\text{aq})

The salt further reacts with water as shown below:-


\text{NH}_4^+ + \text{H}_2\text{O} \rightarrow \text{H}_3\text{O}^+ + \text{NH}_3

Formation of
\text{H}_3\text{O}^+ lowers the pH value of the solution as more hydrogen ions leads to less pH.

User GabMic
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