This week there are 3 investigations for you to carry out. Two are for Rainbow celery and one is to make invisible ink. See if you can be a super scientist and don't forget to send your photographs to firstname.lastname@example.org
Science Investigation-Rainbow celery
Have you ever seen a plant with red or blue leaves? Here's a clever way to make a stick of celery change colour. It will look like magic!
You will need:
sticks of celery with leaves
three small glasses
red and blue food colouring (or other colours)
Instructions for investigation 1:
Instructions for investigation 2:
What has happened?
Plants need water, just like we do. They take up water through their roots. The water travels in little tubes, all the way through the stem to the leaves. if you put dye in the water, the coloured water will be carried to the leaves too.
Now try this:
Put a flower with white petals in water with food colouring. Leave it overnight. What do you think will happen? What did happen? Can you explain why?
Write an invisible secret message that can't be seen and then use chemical reactions to make it appear! Follow the steps below to make your very own invisible ink. Could you send a secret message through the post to a friend or relative and ask them to send one back to you? Pass a secret message to someone in your house too.
You will need:
a small bowl,
a paintbrush or cotton bud
a warm radiator or hairdryer
Many materials, like lemon juice, react when they are heated. This makes them change and sometimes change colour. The juice turns brown as it gets hotter. You can also see this happening when you cook some types of food, such as toast, cake and onions.
Some other materials can also work as invisible ink. Try apple juice, lemonade or white vinegar and investigate to see if they work as well. Which material worked the best as invisible ink?