CHEM 121 Cascadia Community College Acid Base Titration Virtual Lab Report

Chemistry 121 Virtual Lab: Acid-Base TitrationYour Name: Zehra Tosun
Date Lab was performed:
http://chemcollective.org/vlab/103
Objective: To determine the concentration of an unknown acid and an unknown base.
Background: An acid-base titration is a quantitative analysis of acids and bases. Through this process, an
acid or base of known concentration neutralizes an acid or base of unknown concentration.
The titration progress can be monitored by visual indicators, pH electrodes, or both. In this exercise you
will add an indicator to determine the equivalence point.
The reaction’s equivalence point is the point at which the titrant has exactly neutralized the acid or base in
the unknown analyte. If you know the volume and concentration of the titrant at the equivalence point,
you can calculate the concentration of a base or acid in the unknown solution.
Procedure: Record your observations in the data table.
1. Place two 50.0 mL burettes, 0.1M NaOH, 0.1M HCl, unknown acid, unknown base, and
phenolphthalein indicator onto the workbench.
2. Fill the burette with 50.0 mL of 0.1 M NaOH.
3. Add 0.1 M NaOH to the unknown HCl until the pH of the solution reaches 7.0. (Perform a “range
finding” trial by adding 5 mL increments. When you have an idea of the amount of NaOH to add,
perform three trials with at least 0.1 mL precision.)
4. Record the data for three trials. (You will need to add more NaOH to the burette to perform additional
trials. Add more flasks of 0.1M NaOH to the workbench as needed.) Calculate the average
concentration for the three trials.
5. Fill the other burette with 0.1 M HCl.
6. Titrate the unknown NaOH with the 0.1 M HCl until the pH of the solution reaches 7.0. (As
previously, perform a range finding trial and three trials with at least 0.1 mL precision.)
7. Record the data for three trials. (As with the base, you will need to add more HCl to the burette to
perform additional trials. Add more flasks of 0.1M HCl to the workbench as needed.) Calculate the
average concentration for the unknown NaOH.
Acid-Base Titration
DATA TABLE
Show one Molarity calculation
RUN #1
RUN #2
RUN #3
ENDING BURETTE READING (ACID)
STARTING BURETTE READING (ACID)
VOLUME OF ACID USED
MOLARITY OF ACID (from flask)
MOLARITY OF BASE (calculated)
AVERAGE BASE MOLARITY
ENDING BURETTE READING (BASE)
STARTING BURETTE READING (BASE)
VOLUME OF BASE USED
MOLARITY OF BASE (from flask)
JRS Ver. 02.21
MOLARITY OF ACID (calculated)
AVERAGE ACID MOLARITY
Acid- Base Titration Lab Report
Purpose of Lab:
Conclusions
By performing this lab, I learned (describe any new techniques, new equipment, the identity of an
unknown, or a connection to a chemical concept that you learned from this lab.)
By performing this lab, I have formulated the following question that can be tested experimentally. (State
the question and briefly describe how you would experimentally test the question.)
This lab relates to (specifically explain which of the topics, terms, theories, or laws that you have
previously learned that this lab connects with.)
This lab relates to (provide specific examples from the “everyday world” or your personal life that can be
connected with what you learned in this lab and explain how they relate.)
JRS Ver. 02.21