Cabbage Juice pH Experiment

Aaron from the St. Louis Science Center demonstrates how to make cabbage juice, which acts as a pH indicator. The process involves cutting red cabbage, microwaving it with water until it turns dark purple, and then using the juice to test the pH of various substances. By adding ammonia, the juice turns green, indicating a base, while vinegar turns it pink, indicating an acid. The video encourages experimenting with household items to explore their pH levels.

What is the primary purpose of making cabbage juice in this experiment?

• To use it as a food coloring

• To use it as a pH indicator

• To make a refreshing drink

• To use it as a cleaning agent

What is the first step in preparing the cabbage for the experiment?

• Boil the cabbage

• Freeze the cabbage

• Cut or tear the cabbage into chunks

• Add vinegar to the cabbage

How do you know when the cabbage juice is ready after microwaving?

• The water starts boiling

• The cabbage pieces dissolve

• The water turns a dark purplish color

• The water turns clear

What can you do if you want to make more cabbage juice?

• Add more cabbage and water and repeat the process

• Add salt to the existing juice

• Use a different vegetable

• Add sugar to the existing juice

What happens when you add ammonia to the cabbage juice?

• It turns green

• It turns pink

• It turns yellow

• It remains purple

What is the effect of adding vinegar to the cabbage juice?

• It has no effect

• It turns the juice blue

• It turns the juice pink

• It turns the juice green

What is the role of vinegar in the experiment with cabbage juice?

• It acts as a base

• It neutralizes the base and turns the juice pink

• It makes the juice more acidic

• It has no role

What household item is suggested to test with cabbage juice for its pH?

• Salt

• Baking soda

• Sugar

• Oil

What color does the cabbage juice turn when it is neutral?

• Green

• Pink

• Purple

• Yellow

What should you do before experimenting with household items and cabbage juice?

• Use only basic items

• Get permission from parents

• Mix all items together

• Use only acidic items