---
title: "A student titrates a \\(20.00 \\text{ mL}\\) sample of an \\(\\text{HCl(aq)}\\) solution of unknown concentration with a standardized \\(0.100 \\text{ M NaOH(aq)}\\) solution using phenolphthalein as an indicator. The student records the buret readings for three trials in the table below.  | Trial | Volume of \\(\\text{HCl(aq)}\\) (\\(\\text{mL}\\)) | Initial buret reading (\\(\\text{mL}\\)) | Final buret reading (\\(\\text{mL}\\)) | |——-|——————————————-|————————————–|————————————| | 1     | 20.00                                     | 0.50                                 | 10.50                              | | 2     | 20.00                                     | 10.50                                | 20.50                              | | 3     | 20.00                                     | 20.50                                | 30.50                              |  Based on the titration data, what is the molar concentration of the \\(\\text{HCl(aq)}\\) solution?"
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url: "https://nerd-notes.com/ubq/119200/"
date_modified: "2026-08-19T12:39:20+00:00"
---

# A student titrates a \(20.00 \text{ mL}\) sample of an \(\text{HCl(aq)}\) solution of unknown concentration with a standardized \(0.100 \text{ M NaOH(aq)}\) solution using phenolphthalein as an indicator. The student records the buret readings for three trials in the table below.

| Trial | Volume of \(\text{HCl(aq)}\) (\(\text{mL}\)) | Initial buret reading (\(\text{mL}\)) | Final buret reading (\(\text{mL}\)) |
|——-|——————————————-|————————————–|————————————|
| 1     | 20.00                                     | 0.50                                 | 10.50                              |
| 2     | 20.00                                     | 10.50                                | 20.50                              |
| 3     | 20.00                                     | 20.50                                | 30.50                              |

Based on the titration data, what is the molar concentration of the \(\text{HCl(aq)}\) solution?

A student titrates a \(20.00 \text{ mL}\) sample of an \(\text{HCl(aq)}\) solution of unknown concentration with a standardized \(0.100 \text{ M NaOH(aq)}\) solution using phenolphthalein as an indicator. The student records the buret readings for three trials in the table below.

| Trial | Volume of \(\text{HCl(aq)}\) (\(\text{mL}\)) | Initial buret reading (\(\text{mL}\)) | Final buret reading (\(\text{mL}\)) |
|-------|-------------------------------------------|--------------------------------------|------------------------------------|
| 1     | 20.00                                     | 0.50                                 | 10.50                              |
| 2     | 20.00                                     | 10.50                                | 20.50                              |
| 3     | 20.00                                     | 20.50                                | 30.50                              |

Based on the titration data, what is the molar concentration of the \(\text{HCl(aq)}\) solution?

- **A.** \(0.0500 \text{ M}\)
- **B.** \(0.100 \text{ M}\)
- **C.** \(0.200 \text{ M}\)
- **D.** \(0.400 \text{ M}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119200/*