Hi my name’s Michael and I’m here in the House Secrets kitchen at Scienceworks.
2011 is the International Year of Chemistry and that’s with good reason, because chemicals are in absolutely everything.
We make use of chemicals all the time without even realizing it.
So we’re going to take a look at some chemicals around your house.
Some of the chemicals around your house are acids and vinegar is an example of an acid that you can find at home.
And some of the chemicals around your house are bases. Soap is a base that you can find around your home.
One way that we can test if something is an acid or base is to use red cabbage as an indicator.
To make the red cabbage indicator first put some chopped cabbage in a jug and then pour some boiling water over it. So now just set the cabbage aside for about 20 minutes and let it seep in the boiling water.
Strain the liquid into another jug like so and your indicator is now ready
We know that vinegar is an acid so let’s see what colour the indicator will go if we put it in some vinegar. As you can see it goes a red colour.
We know that soap is a base, so let’s see what happens when we add some indicator to soapy water. And its turned a blue colour.
So we know that vinegar an acid turns red and the soap a base turns blue.
I’ve got some bicarbonate soda here –so is that an acid or a base? Let’s find out. First of all dissolve it in some water. Now we’ll add the indicator. Bicarbonate soda turns blue so we know it’s a base.
How about lemonade? Is lemonade an acid or a base? Let’s find out. Once again I’ll add the indicator to the lemonade. Okay so lemonade has gone a pink colour which means it’s a weak acid. Even though the lemonade tastes sweet but that’s because it got added sugar.
So finally let’s see what happens with water. I’ve got some water in a jug here so let’s add some indicator. As we can see it doesn’t change colour because water is neither an acid nor a base. It’s what we call neutral and therefore it belongs in the middle.
So when we add an indicator to an acid it will change one colour and when we add it a base it will change another colour.
For further information download the activity sheet and to find more about the chemistry happening around your house, come along to House Secrets. Have a great International Year of Chemistry and I look forward to seeing you here at Scienceworks.