WHAT IS HAPPENING HERE?
PREDICT: Ask your
students "What colour is the ink in this bottle? Will happen if I shake
OBSERVE: Shake the
bottle (being careful not to drop it!) quite vigorously.
EXPLAIN: What does this
show us? (seniors might like to consider the chemical reaction involved
WHY THE COLOUR CHANGE? IT"S CHEMISTRY!
If you vigorously shake the bottle it turns blue. Left
for a while it returns to a colourless solution. The reason this
happens is that the oxygen combines with the Methylene Blue causing a
reversible colour change.
This colour change is due to a set of reversable
chemical reactions, known as REDOX reactions.
See Magic Bottle II for
FIND OUT MORE:-
- Try the other recipe for a
"magic" bottle here...
- Find out more about "redox" reactions
- The interactive pages...identify these pieces of lab
- The interactive pages...weird metals and gases hide
in this Periodic Table