---
title: "A student titrates a \\(25.00 \\text{ mL}\\) sample of an acidified \\(\\text{Fe}^{2+}\\text{(aq)}\\) solution of unknown concentration with a standardized \\(0.0500 \\text{ M } \\text{KMnO}_4\\text{(aq)}\\) solution. The balanced equation for the reaction that occurs during the titration is shown below.  \\[ \\text{MnO}_4^-\\text{(aq)} + 5\\text{Fe}^{2+}\\text{(aq)} + 8\\text{H}^+\\text{(aq)} \\rightarrow \\text{Mn}^{2+}\\text{(aq)} + 5\\text{Fe}^{3+}\\text{(aq)} + 4\\text{H}_2\\text{O(l)} \\]  If the faint pink endpoint is reached after exactly \\(10.00 \\text{ mL}\\) of the \\(0.0500 \\text{ M } \\text{KMnO}_4\\text{(aq)}\\) titrant is added, what is the concentration of \\(\\text{Fe}^{2+}\\text{(aq)}\\) in the original sample?"
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url: "https://nerd-notes.com/ubq/123685/"
date_modified: "2026-09-28T12:01:58+00:00"
---

# A student titrates a \(25.00 \text{ mL}\) sample of an acidified \(\text{Fe}^{2+}\text{(aq)}\) solution of unknown concentration with a standardized \(0.0500 \text{ M } \text{KMnO}_4\text{(aq)}\) solution. The balanced equation for the reaction that occurs during the titration is shown below.

\[ \text{MnO}_4^-\text{(aq)} + 5\text{Fe}^{2+}\text{(aq)} + 8\text{H}^+\text{(aq)} \rightarrow \text{Mn}^{2+}\text{(aq)} + 5\text{Fe}^{3+}\text{(aq)} + 4\text{H}_2\text{O(l)} \]

If the faint pink endpoint is reached after exactly \(10.00 \text{ mL}\) of the \(0.0500 \text{ M } \text{KMnO}_4\text{(aq)}\) titrant is added, what is the concentration of \(\text{Fe}^{2+}\text{(aq)}\) in the original sample?

A student titrates a \(25.00 \text{ mL}\) sample of an acidified \(\text{Fe}^{2+}\text{(aq)}\) solution of unknown concentration with a standardized \(0.0500 \text{ M } \text{KMnO}_4\text{(aq)}\) solution. The balanced equation for the reaction that occurs during the titration is shown below.

\[ \text{MnO}_4^-\text{(aq)} + 5\text{Fe}^{2+}\text{(aq)} + 8\text{H}^+\text{(aq)} \rightarrow \text{Mn}^{2+}\text{(aq)} + 5\text{Fe}^{3+}\text{(aq)} + 4\text{H}_2\text{O(l)} \]

If the faint pink endpoint is reached after exactly \(10.00 \text{ mL}\) of the \(0.0500 \text{ M } \text{KMnO}_4\text{(aq)}\) titrant is added, what is the concentration of \(\text{Fe}^{2+}\text{(aq)}\) in the original sample?

- **A.** \(0.100 \text{ M}\)
- **B.** \(0.160 \text{ M}\)
- **C.** \(0.250 \text{ M}\)
- **D.** \(0.625 \text{ M}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/123685/*