There are many chemicals around the home that are used for cleaning and other special jobs. Some of these are very strong and can be harmful. If they are they will have special symbols on them to warn you like the one below.
The symbol above means that if you splash this chemical on anything (including yourself) it will burn holes in it. These substances are normally only handled by adults and you should never play with them.
There are a lot of different safety symbols used to warn us about dangerous materials. Try the next quiz to see how much you know.
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Finally, there are weak acids. These taste sour and sting if you get them into cuts. In fact most sour or sharp tastes are due to acids in the food we're eating. Yes, some acids are edible, in fact later I'll give you a recipe for an edible acid you can make and eat in your own kitchen.
Sour foods like sherbet taste sour due to the the acid in them; sherbet has citric acid in it. This is mixed with 'bicarb' (an ingredient used to make cakes). Nothing happens to these two ingredients until water is added, then they dissolve (link to dissolving page) and a reaction occurs (link to changes & reactions page).
A gas called carbon dioxide (link to carbon dioxide, discovery, uses, Joseph Priestley page) is then released into your mouth when the sherbet gets wet. The fizziness you feel is due to the carbon dioxide gas escaping and bubbling through your saliva (spit).
Carbon dioxide also causes the fizziness of fizzy drinks. Often, stronger acids (usually citric acid or phosphoric acid) are added to fizzy drinks to make them even more tingly. Unfortunately, this makes them taste very sour so loads of sugar is added to make them taste better.
The combination of loads of sugar and acids in fizzy drinks is what makes them so bad for our teeth. Why not ask your dentist about this and how brushing your teeth properly can prevent this damage.
You can see how much fizzy drinks damage your teeth with the next experiment.
Science Of Acids Part 2