What Are Indicators & How Do We Use Them?

The video tutorial explains how to determine the pH of a solution using indicators. It covers universal indicators, which show a range of colors across the pH scale, and specific indicators like litmus, phenolphthalein, and methyl orange, each with distinct color changes at certain pH levels. The tutorial concludes with a summary of how indicators work and their importance in identifying the pH of solutions.

What is the primary function of a pH indicator?

• To dissolve in water

• To indicate the pH level by changing color

• To change the pH of a solution

• To measure temperature

What does a deep red color in a universal indicator signify?

• The solution is strongly alkaline

• The solution is weakly alkaline

• The solution is strongly acidic

• The solution is neutral

How does blue litmus paper react in acidic conditions?

• It turns blue

• It turns red

• It remains unchanged

• It turns green

At what pH does phenolphthalein change from colorless to pink?

• 8.2

• 3.1

• 7.0

• 4.4

What color does methyl orange turn at a pH higher than 4.4?

• Red

• Blue

• Green

• Yellow