Hello Creative Kids,

I hope that you have a spare cape because today’s Science Superhero activity requires the help of a grown-up.

Today we are going to learn about pH levels in household liquids.  So what is pH? 

pH is a scale that scientists use to measure how much acid is in something. If something is acidic it has a high pH and if it is alkaline (or basic) it has a low pH level.  The scale ranges from 0 being the most acidic to 14 being the most alkaline.  Pure water should sit right in the middle at 7, being neutral meaning that it is neither acidic nor alkaline.

 

Today we are going to use red cabbage to make our own pH indicator. Red cabbage contains a water-soluble pigment called anthocyanin that changes colour when it is mixed with an acid or an alkaline solution. The pigment turns red in acidic environments with a pH less than 7 and the pigment turns bluish-green in alkaline (basic) environments with a pH greater than 7.

So let’s get started.

What you need:

  • An adult
  • ¼ of a red cabbage
  • A mixing bowl
  • Boiling water
  • A blender
  • A strainer
  • Clear cups
  • An assortment of household liquids or powders that you could make a solution with.

What to do:

Chop up your cabbage and put into a heat proof mixing bowl.

Pour boiling water over the cabbage and allow it to sit for a few minutes.

Pour the cabbage and the water into your blender and give it a good whiz.

Stain the liquid into a jug, removing all the bits of cabbage.  Now you have your pH indicator.

Here’s the fun bit. Place different liquids from around your how into clear glasses don’t forget to label each one.  I used; tap water, mineral (sparkling) water, tonic water, lemon juice, bleach, dishwashing liquid, surface spray, bi-carb soda, and hand sanitiser.

Check out the results!

My results were quite interesting.  I was surprised that hand sanitiser was almost the same as tap water.  The funniest result was that the bleach would change colour, but then quickly returned to its original colour – the bleach was bleaching the pH indicator.  What other household products would you use?

That’s it for Science Superheroes this month. I can’t wait to hear about all the different experiments you have done at home.

Next week we’ll be looking at Brilliant Boardgames.

Take care Creative Kids,

Carlie