这是一篇加拿大幼儿化学学习教案
Acidic and Basic Test
Suggested Grades -1
Objective Students will be introduced to acidic and basic liquids through this simple test.
Materials
clear plastic cups
a head of purple cabbage coarsely shred.
spoons
paper towels
*safety glasses
white vinegar
ammonia
water
Method Can do this activity as a demonstration or in class groups. Take extra care with the ammonia, though.
Boil the shredded cabbage in a 1/2 a pot of water for about ten minutes. Strain and refrigerate until ready to use.
Fill cups about half way with each liquid.
Add one teaspoon of the boiled cabbage to each glass. What happened?
Cabbage should change colour:
vinegar - red - acid
ammonia - green - base
water - purple - neutral
Based on these colour changes, try to predict whether other liquids are acidic or basic, then add the boiled cabbage to find out. Extension: Make your own indicator paper.
Soak paper towels or white coffee filters in purple cabbage juice.
Let dry and cut into strips. The strip should change colour according to the type of liquid it's dipped into. | |
