Chemistry - Titrations/Pre-lab

What is titration

an analytical process used to determine the unknown molarity of a chemical by completely reacting it with a known molarity and volume of another chemical.

What is analyte

the chemical with the unknown molarity

What is titrant

the chemical with a known molarity and volume used to react with the analyte.

the two chemicals are usually

acid and bases (titrant and analytes)

the third chemical is the

Indicator that signals the endpoint of the titration.

What is the equivalence point?

The analyte is completely used by the titrant meaning that the experiment is complete.

What is the end point?

When color change occurs (indicatior)

Equipment used:

Buret, buret clamp, pipette, Erlenmeyer flask, ringstand, and magnetic stirrer.

What is the purpose of the lab?

To begin with a known volume of hydrochloric acid that has an unknown concentration and slowly add a standard sodium hydroxide solution (known concentration) until you reach end point.

formula for molarity?

M=n/L

neutralization reaction

Acid + Base ←→ Water + Salt

Safety Precautions

Wear goggles, lab coat, keep long hair tied, and wear long pants. Handle and dispose with care.

What color will bromothymol blue be at pH of 7?

Green

What color will bromothymol blue in the presence of an acid?

Yellow

What color will bromothymol blue in the presence of an base?

Blue

What color will phenolphthalein be at pH of 7?

Colorless

What color will phenolphthalein in the presence of an acid?

colorless

What color will phenolphthalein in the presence of an base?

magenta