Chemical Reactions and Indicators

The video tutorial demonstrates an experiment involving 0.1 molar hydrochloric acid and sodium hydroxide solutions, using phenolphthalein as an acid-base indicator. The instructor first tests sodium hydroxide with phenolphthalein, observing a color change. Then, hydrochloric acid is added to the sodium hydroxide solution, resulting in another visual change. Throughout the experiment, no significant changes in temperature or sound are noted.

What is the concentration of the hydrochloric acid used in the experiment?

• 2 molar

• 0.5 molar

• 1 molar

• 0.1 molar

Which indicator is used in the experiment to observe changes?

• Litmus

• Phenolphthalein

• Methyl orange

• Bromothymol blue

What is the appearance of sodium hydroxide before adding phenolphthalein?

• Clear colorless liquid

• Yellow liquid

• Red liquid

• Blue liquid

What kind of change is observed when phenolphthalein is added to sodium hydroxide?

• Temperature change

• Sound change

• Visual change

• No change

What happens when hydrochloric acid is added to the sodium hydroxide solution with phenolphthalein?

• No change occurs

• A sound is heard

• A visual change occurs

• A temperature change occurs

What is the appearance of hydrochloric acid before it is added to the sodium hydroxide solution?

• Blue liquid

• Clear colorless liquid

• Yellow liquid

• Red liquid