Acid-Base Indicators and Their Colors

The video tutorial explains acid-base indicators, substances that change color based on the acidity or basicity of a medium. These indicators are used in acid-base titrations to determine the pH of a solution. The video details how different indicators, such as phenol styling, neutral red, congo red, methyl red, gentian violet, methylene blue, and a universal indicator, change colors in acidic and basic environments. Each indicator has distinct color changes, which are crucial for identifying the pH level during chemical experiments.

What is the primary use of acid-base indicators in chemistry?

• To measure temperature changes

• To conduct acid-base titration experiments

• To identify metals

• To determine molecular weight

What ion is formed when an indicator reacts with an acid?

• H2O

• INO-

• HIN+

• OH-

Which color does phenol styling exhibit in a basic medium?

• Colorless

• Pink

• Yellow

• Red

In which medium does neutral red appear yellow?

• Acidic

• Neutral

• Basic

• None

What color does congo red turn in an acidic medium?

• Violet

• Red

• Blue

• Yellow

Which indicator is red in both acidic and basic mediums?

• Phenol Styling

• Gentian Violet

• Congo Red

• Methyl Red

What color does methyl red exhibit in a basic medium?

• Blue

• Violet

• Yellow

• Red

In which medium does gentian violet appear yellow?

• Neutral

• Basic

• None

• Acidic

What is the color of methylene blue in an acidic medium?

• Yellow

• Blue

• Violet

• Red

What color does a universal indicator show in a basic medium?

• Red

• Yellow

• Violet

• Blue or Gray