TITRATION

Andy Park

What is Titration?

A method of quantitative chemical analysis used to calcu-late concentration

A known concentration and volume of titrant reacts with a solution of analyte or titrand to determine the conentration.

How titration works: When the base or acid of known con-centration meets with the unknown acid or base, the pH slowly changes By calculating how much acid reacts with how much base, we can find out the concentration of the unknown.

ACID + BASE = WATER + SALT

SETUP

PROCEDURE

Titration begins with a beaker or a Erlenmeyer flask containing a precise volume of the analyte with a small amount of indicator placed

Then the analyte is placed under a calibrated burette containing the titrant

Small values of the titrant are added to the analyte

When the indicator changes color, that marks the end of the titra-tion

Types of Titration

Acid – BaseRedox

Gas-PhaseComplexometric

Zeta potential

Mainly Used

Choose the right indi-cator

TIPS

When using large quantities of both titrant and unknown, you can quickly finish the first experiment, giving you a simple idea of where the color changes

Even if the experiment was perfect in the first trial, repeat to reduce error

Make sure the walls of the beaker or flask doesn’t contain unreacted titrant during the experiment, this can be fixed by running deionized water on the walls of the flask. Small amounts of water will not change the outcome of the titration

Label the unknown and titrant so you don’t mix up the data table

Bubbles in the burette tip can usually be removed by tapping the side of the burette while the stopcock is open

Placing something white can help with spotting the color change

SAMPLE QUESTIONS

You have a 25 mL solution of 0.5 M NaOHIt is titrated until neutralized into a 50 mL sample of HCl

Determine the concentration of HCl

A 15.00 mL sample of acetic acid is titrated with 34.14 mL of 0.9940 M NaOH

Determine the molarity of the acetic acid