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webshed.org

Probably - but let’s experiment anyway. In the Autumn (Fall in another part of the world), the leaves on the trees change colour from green to not-as-green-perhaps-red. Red organic compounds are somewhat pH sensitive - you’ve probably seen the experiment where the extract from red cabbage is made to change colour with the addition of vinegar or baking soda. Can we do the same with leaves? Extracting the colour from leaves I know from years of experience that alcohol will extract the chlorophyll from green leaves, so I’ll try it to exact the red stuff. Some autumn leaves Chopping the leaves increases the surface area and helps the solvent penetrate the cut edges instead of the waxy, flat surfaces. I ended up stirring the leaves in a warm 50% ethanol solution (25ml of methylated spirit and 25ml of water). chopped_leaves in a beaker with solvent There should have been a video here but your browser does not seem to support it. The extract is quite yellow (#TeamYellowChemistry). The red components don’t dissolve as well but have faded in the leaves. The dilution in the alcohol solution may reduce the strength of the colour. After filtering to remove the leaf bits, the solution is a slightly cloudy yellow. I could have tried to spin this down in a centrifuge to clean up the cloudiness, but this was just a quick experiment to kill time on a dull afternoon when I should have been doing something more useful. Filtered extract from the leaves Adding some dilute 0.1M hydrochloric acid to the extract causes a colour change toward red / orange There should have been a video here but your browser does not seem to support it. I also added a dilute sodium hydroxide solution to some of the extract - this caused the extract to turn dark Acid - Neutral - Base While not very quantitative and not something you could use in a lab setting, I did at least prove to myself that the c

dhlpilotcentral.com

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dzkit.com

over the years, one by one, all the great electronic kit manufacturers have disappeared - eico, knight, dynaco, heath. perhaps the most devastating for the home electronics enthusiast was the loss of heathkit®, a mainstay from 1947 to the mid-1980's.

k4icy.com

welcome to the home site of k4icy, amateur radio operator & designer - mike maynard in panama city, florida, usa

parts.arrow.com

arrow.com is your resource for electronic component products, datasheets, reference designs and technology news. explore arrow.com today.

analog.com

analog devices is a global leader in the design and manufacturing of analog, mixed signal, and dsp integrated circuits to help solve the toughest engineering challenges.

minikits.com.au

mini-kits is australia's largest supplier of electronic kits and components to radio experimenters, engineers, and amateur radio enthusiasts.