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THE SCIENCE LAB
Make & Do Activity Kit
500 Harris St Ultimo
PO Box K346 Haymarket NSW 1238
Australia
Tel: 02 6217 0111
http://play.powerhousemuseum.com
This work is licensed under the Creative
Commons Attribution-NonCommercial-
ShareAlike 2.5 License.
Homemade litmus paperLitmus paper is used in many simple experiments to test
or PH balance. When dipped into dierent substances itwill turn dierent colour according to how acidic or basic
it is. It is sometimes called acid-indicator paper.
Time:1+ hrs
Difculty:
Hints: Remember that some household substancescan be harmul to eyes and skin so this is an activity
to do with adult permission and supervision.
Adult or supervised step:
Chop some red cabbage
leaves into small pieces and
place in a saucepan. Pour
water over the cabbage and
simmer or 20 minutes.
1.
To prepare your test
substances place each
separately in a dish or cup.
Powdered substances need
to be mixed with a little
water. Label each clearly.
2.
When the red cabbage
mixture has cooled, place
the seive over the large
bowl, strain the cabbage
and collecting the liquid.
Allow to cool until warm.
3.
Soak each strip into the
cabbage sollution and lay it
onto the old tea towel to dry.
4.
Arrange labelled test dishes
in a row on scrap paper.
Place a litmus strip in ront
o each test dish. Dip each
into a bowl or 5 seconds.
5.
Watch the colours change
on the litmus papers.
Compare them to the ph
chart on page 3. Choose
more substances to test
rom our suggestion list.
6.
a chopping board
a knie
a saucepan
1 litre o water 1 dish or cup or
each test substance
(suggested list below)
Pen and paper
large plastic bowl
a seive
blotting or watercolourpaper (cut into10cm x
3cm strips)
old tea towel & paper
What you will need:
500 Harris st. Ultimo
PO Box K346 Haymarket NSW 1238Australia Tel: 02 9217 0111
http://play.powerhousemuseum.com
Creative Commons Licence for use of this work
This work is licensed under a Creative Commons Attribution-NonCommercial 3.0 Australia Licence (CC BY-NC 3.0 AU)
http://creativecommons.org/licenses/by-nc/3.0/au/
Household substances to test: lemon juice
shampoo
orange juice
white vinegar laundry detergent or
powder
bicarb soda
tartaric acid or citric
acid
milk
egg whites toothpaste
lemonade
tap water
7/29/2019 Red cabbage litmus paper
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Page 2
500 Harris St Ultimo
PO Box K346 Haymarket NSW 1238
Australia
Tel: 02 6217 0111
http://play.powerhousemuseum.com
This work is licensed under the Creative
Commons Attribution-NonCommercial-
ShareAlike 2.5 License.
THE SCIENCE LAB
Make & Do Activity Kit
Homemade litmus paper
What else can i do?
Activity 1: Record your results.
Recording test results is important or observing
and comparing outcomes o dierent tests. It allows
you to nd answers to questions and come to
conclusions.
You have used strips o litmus paper to testsubstances around the house. Now create a result
table to sort your ndings into acids, neutrals and
bases.
Use the PH scale on the next page to order your test
substances into acid, neutral and base by matching
up the colours.
Activity 2: Create decorating craft paper.
This is a simple variation and results in beautiully
colored paper that can be used or art projects likecollages. Here is an example we prepared using a
litmus paper painted with lemon juice, baking soda
sollution and white vinegar.
Acid, neutral or base?
Whats going on?
Chemicals can be either an acid,
a neutral or a base. In order totest i something is an acid or a base we can use an
indicator. An indicator will change in colour when it
goes rom a neutral condition to an acidic or basic
condition and can tell us the pH o dierent things.
Red cabbage contains a natural pigment molecule
called favin which changes colour when it comes
into contact with acids and bases. We call this
chemical a pH indicator.
The indicator changes rom purple to bright pink in
acids to blue or green in bases. Using the changingcolours we can create a pH scale which numbers 1
to 14.
When a chemical has a pH o 7 it is neither an
acid or a base and it is called neutral. Water is
considered neutral. It is important to note that the
indicator itsel might not be neutral.
Lemon juice and vinegar are both acid so they will
turn the litmus paper pink. Baking soda turns a
green/blue colour indicating a base is present.
500 Harris st. Ultimo
PO Box K346 Haymarket NSW 1238Australia Tel: 02 9217 0111
http://play.powerhousemuseum.com
Creative Commons Licence for use of this work
This work is licensed under a Creative Commons Attribution-NonCommercial 3.0 Australia Licence (CC BY-NC 3.0 AU)
http://creativecommons.org/licenses/by-nc/3.0/au/
7/29/2019 Red cabbage litmus paper
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Page 3
500 Harris St Ultimo
PO Box K346 Haymarket NSW 1238
Australia
Tel: 02 6217 0111
http://play.powerhousemuseum.com
This work is licensed under the Creative
Commons Attribution-NonCommercial-
ShareAlike 2.5 License.
THE SCIENCE LAB
Make & Do Activity Kit
Homemade litmus paper
500 Harris st. Ultimo
PO Box K346 Haymarket NSW 1238Australia Tel: 02 9217 0111
http://play.powerhousemuseum.com
Creative Commons Licence for use of this work
This work is licensed under a Creative Commons Attribution-NonCommercial 3.0 Australia Licence (CC BY-NC 3.0 AU)
http://creativecommons.org/licenses/by-nc/3.0/au/
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