Acid Base Titrations

Acid-Base Titrations

Hunter Pauly, Garrett Stavang, and Luke Vine

Acid-Base Titrations

Hunter Pauly, Garrett Stavang, and Luke Vine

Objectives:

1) To become familiar with the methods of volumetric analysis.

2) To standardize a basic solution using acid-base titrations.

Material List:

* Safety Goggles

* 250 mL beakers (2)

* 50 mL Buret (2)

* Buret Holder

* 250 mL Flask

* Ring Stand

* 1 Gram Potassium Hydrogen Phthalate (KHC8H4O4)

* Distilled Water (H2O)

* NaOH

* HCl

* Phenolphthalein

* Electric Balance

* Funnel

* Plastic Holder

* Two Stopcocks (2)

Procedure:

Part I: Standardization of a NaOH Solution

1) To a clean, dry beaker, add about 100 mL of the NaOH solution you standardize. Thoroughly clean a buret by rinsing it with water several times. A clean buret will drain evenly, without leaving water spots on the glass wall. When the buret is clean, rinse the inside surface twice with a few mL of the NaOH solution to be standardized. This will ensure that the NaOH concentration will be the same throughout the buret. With the stopcock closed, carefully fill the buret with the NaOH solution. Drain some of the solution until the liquid level is about to the 0 mL mark. Read and record the buret level to the nearest 0.1 mL.

2) Weigh out about 1 gram of potassium hydrogen phthalate, KHC8H4O4, to the nearest .01 gram on a weighted piece of filter paper. Pour the solid into a clean 250 mL Erlenmeyer flask. Add about 30 mL of distilled water and swirl the flask until all of the solid dissolves. Wash any crystals which cling to the wall of the flask down into the solution with distilled water from a wash bottle. Add two drops of phenolphthalein indicator to the aid solution.

3) Place the flask under the buret, then lower the buret until its tip extends into the flask. Place a piece of white paper beneath the flask to help you see color changes. Titrate the solution, gradually adding base...