How did Boyle invent the acid base test strip?

In Boyle's laboratory, a dark purple, very beautiful violet suddenly smoked. When I looked closer, it turned out that the concentrated hydrochloric acid used for the experiment was splashed on the flowers. Boyle immediately picked up the bouquet and washed it in water.

As a result, a magical miracle happened! The violet turned red and became the "red rolan".

This serendipitous discovery caused Boyle to seriously ponder: if violets encountered other acid solutions, would this phenomenon also occur. If not violets but other colored plants.

What would happen if the colored plants encountered not acids, but alkalis, the opposite of acids?

Boyle's only solution to this chain of problems was experimentation. So, he asked his assistants to leave the laboratory and go to the garden and field to collect all kinds of colored plants. When the assistants returned, the lab was almost a flower room.

Not only the best violets are found here, but also roses, primroses, magenta, litmus, turmeric, sumac, gallnut and many more. Boyle and his assistants first impregnated the sap of these colored plants, and then reacted the infusion with acids and alkalis, respectively. Some only change color under the action of acid, while others change color when exposed to alkali.

The most interesting thing is that the purple litmus infusion turns red when exposed to acid and blue when exposed to alkali. In this way, it is not possible to use these plant infusions to identify what is an acid and what is a base? These infusions are acid-base indicators.

For the sake of ease of use, Boyle also came up with a method of using paper that absorbs the immersion and then dries it to test the acidity and alkali. The litmus test paper, which is still in use today, was invented by Boyle.

In this study, he further learned that in addition to acid-base reactions, there are many chemical reactions that can produce colored substances. With these color variations, more substances can be examined. For example, when a solution of silver nitrate meets hydrochloric acid, a white precipitate (i.e., silver chloride, which Boyle called "crescent" at the time).

Potassium carbonate solution (alkali in plants) reacts with mercuric chloride to produce a yellow precipitate. Add some ammonia to the copper salt solution, the blue color will become significantly darker, if the copper salt is burned on the fire, the flame will appear green, and so on.

Analytical chemistry is to test the composition and content of analytical substances. Boyle's above discoveries laid a good foundation for the development of analytical chemistry. Therefore, people respectfully call him the founder of analytical chemistry.

Acid-base test strips were invented by Boyle! Because while they were experimenting, an assistant accidentally splashed a drop of hydrochloric acid on the violets, and after a while, the petals splashed with hydrochloric acid miraculously turned red, and Boyle immediately became sensitive to the fact that there was a substance in the violet that would turn red when it met hydrochloric acid. Boyle asked many questions, which prompted Boyle to conduct many experiments.

Finally, Boyle made an acid-base test paper, a litmus test paper, which is commonly used in experiments. Since then, this test strip has been widely used in chemical experiments.

The order of these three events in the sixth and fifteenth lessons is to write first about the observed phenomena, then to write about a series of questions, and finally to write about the discoveries and inventions after experiments.

The acid-base indicators commonly used in chemical experiments were discovered because of his careful observation. During a tense experiment by Boyle, the violets placed in the laboratory were splashed with concentrated hydrochloric acid, and Boyle quickly washed the smoking violets with water, and found that the dark purple violets had turned red.

This strange phenomenon prompted him to carry out many experiments on the interaction of flowers and trees with acids and bases. As a result, he discovered that most flowers and plants can change their color when affected by acid or alkali, and the purple infusion extracted from litmus is the most obvious, which turns red when exposed to acid and blue when exposed to alkali. Taking advantage of this feature, Boyle made an acid-base test paper commonly used in experiments—litmus paper.