Acids and Bases: What happens when H+ ions dissociate
Today was all about acids and bases. Students put on their safety goggles and investigated how scientists classify acids and bases using the pH scale. The lesson began by teaching our young scientists about ions, an atom that loses or gains an electron. Once atoms become ions and are charged, they can attract or repel each other, like magnets. This is how acids and bases react. We introduced the pH scale, so they understood how scientists measure the acidity or basicity of a solution.
We tested the pH of several common substances found in every day life, including ammonia, vinegar, cola, baking soda, borax and milk. We did this using pH paper which could give us a pH reading on the 0-14 scale that we we to measure pH. The young scientists were shocked to discover that some solutions were extremely acidic or basic and found that soda is very acidic–sugar isn’t the only reason it is bad for your teeth!
Near the end of the lesson we used a strong acid to remove the tarnish off of a penny (a reaction involving the zinc in the penny, not the copper) and then set up a mini volcano by combining an acid (we used citric acid but at home you could use vinegar) with a base (baking soda)- fun explosion!
Additional Information:
This is an AWESOME video about what happens to an “aluminium” coke can in a strong acid (HCl “hydrochloric acid”) and a strong base (NaOH “sodium hydroxide), the same liquids you saw today!
http://www.youtube.com/watch?v=WnPrtYUKke8
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