How do you make a strawberry blonde?
Why, hydrogen peroxide of course!
We have been doing some experiments with strawberries recently. First we wanted to look at the effect of freezing on strawberries.So we did an experiment where we observed what happened when a frozen strawberry (on the left) and a chilled strawberry (on the right) were allowed to warm up to room temperature side by side. Here’s an animation of the warming up process: The ice crystals in the frozen strawberry have destroyed much of the internal structure of the strawberry such that it collapses into a mush, oozing out juice on thawing.
Our second experiment looked at what happened when a strawberry was placed in hydrogen peroxide bought from a local pharmacy. Take care to read the safety precautions on the label when using hydrogen peroxide. Hydrogen peroxide can be used to take the colour out of hair or a strawberry. Hey presto, a white strawberry. The bleached strawberry still smelled like a strawberry. Do not eat!
Our third experiment was a combination of the first two experiments. We decided to look at the effect of temperature on the bleaching process. Accordingly, we dipped a frozen strawberry and a room temperature strawberry into hydrogen peroxide side by side. We measured the temperature difference between the two beakers. And we watched what happened. After about thirty minutes the cold one had warmed up a little. And the warmer strawberry had lost more colour than the frozen one. Increasing the temperature, increased the rate of reaction. In this case the bleaching of a strawberry. Although the loss in colour was not even across the surface of the strawberry in this experiment.
Last time I asked which metals were unlikely to react with 2M hydrochloric acid? The best answer is to pick metals such as gold and platinum at the bottom of the reactivity series. This would be an expensive experiment to carry out though.