The iodine will complex with the starch in the paper and
turn purple. The lemon juice painted sections will remain white. Caution:
Iodine will stain almost anything it touches brown and is not an easy
stain to remove.
Don't have any Iodine? Try this:
PREDICT: Ask your
students "What will happen when I take this blank piece of paper and
heat it over this candle flame?"
OBSERVE: Watch what
happens with careful heating
EXPLAIN: What does this
show us? (seniors might like to consider the chemical changes involved
or consider carrying out a titration that uses Iodine
Children must be very be careful and ask the help of an
adult to do this!
Want to try something else? Try making a "normal" ink from tea...