Question

1 example of useless mixture
4 examples of useless mixture

Answer 1

Explanation:

In chemistry, when two or more substances mix with each other without participating in a chemical change, the resulting substance is called a Mixture

Answer 2

Answer:

The Transuranics: Berkelium (Element 97) and Up

The Transuranics: Berkelium (Element 97) and Up

As the name would suggest, the transuranics are those elements with atomic numbers higher than that of uranium, and are typically synthesized in a lab. While neptunium through curium have their places, mostly in nuclear power, berkelium starts a sea of relative uselessness. The elements beginning with einsteinium and going up, in fact, have never been spotted in nature. Most have half-lives of a minute or even fractions of a second, which factors into their not-so-abundant nature.

Uses: Physicists believe that there may be an "island of stability" above these elements with comparatively prolonged half-lives. You know, if we could manage to make the darn things. To that end, creating and studying the transuranics in the lab is a step toward one day perhaps finding even heavier elements.