onsdag 21 maj 2014
I did these experiments/read this information as a part of the last chapter of kitchen chemistry.
A Catalyser is something used to speed up a chemical reaction without getting involved in it. And it lets chemical reactions start with less energy (heat). Enzymes, wich are found in our saliva (Yuck) is a sort of biological catalyser. For example, chew a piece of bread, chew it for a time, and keep it there. Soon you will notice that the bread will taste more sweet than before. That is because the catalyser, our enzymes, break down amylose, and starch.
Heres a small explanation by Stephen Ashworth, Kitchen chemistry host.
"Some of the catalysts we use routinely are not synthesised by chemists though. Biological washing powders contain enzymes which are used to digest fatty stains. Usually washing is done at temperatures above body temperature and enzymes only have a limited temperature range in which they work efficiently, so the enzymes used in washing powders are likely to have been harvested from organisms adapted for life in hot springs (such as those in Yellowstone National Park. Biological detergents might contain one or more of four different enzymes. An amylase to digest starch, a cellulase to digest cellulose, a protease to digest proteins and a lipase to digest fats."
1 The first experiment was not the kind of safe experiments you do with bicarbonate and lemon juice. No, this was something really dangerous. I only watched the video for it on the website.
You have a glass jar, and fill a sixth of it with acetone (AKA nail polish remover).
Then you heat a piece of copper (Cu 29) until it is glowing red. then you carefully put it over the acetone, NOT in it, this can explode. You will notice that the red strip of copper will continue glowing red with heat. This is because the acetone reacts with oxygen. check up the video here:
In this experiment i used a glass, with a sixth of water. Then i poured in some hydrogen peroxide. Then i put in a piece of potato, The enzyme in the potato is our catalyser in this case. Now, the potato will begin to float in the hydrogen peroxide (H2O2). This is because the enzymes turn the h2o2 into water and oxygen!
For this experiment, i used a solution of yeast and water. i poured the yeast and water into a glass, and added a few drops of washing up liquid, this is to assure that the experiment can be properly observed, and poured in some h2o2. Now, the h2o2 will vapor because of the yeast enzymes, and this will be shown as the bubbles of the washing up liquid. if you turn te glass upside down after a while, you will notice that the bubbles are pretty thick and strong.
Thats all, i guess! see you next time!
Upplagd av Sagor och drakar kl. 02:42