[Alghranokk]

This entire comment is, i am sorry to say, silly. ou are arguing that the element bismuth should be called a "semimetal" as opposed to a "metal", and in a sense, you are correct.

in another sense, however, it would also make sense to call it and every other element heavier than helium "metal"; since that is how things are done in astronomy, where the arguably most important elements are the first ones.

But when one reads "metal" without any other context, one generally interprets the term within the context of chemistry, where bismuth is absolutely referred to as a "metal", a "post-transition metal" to be more precise.

That is to say, you are the botanist showing up and calling the tomato a fruit, wheras the rest of the world understandably calls it a vegetable.

[adrian_b]

One can choose to classify the chemical elements with whatever words one pleases.

Nevertheless, some classifications are much more useful than others.

A classification that no longer uses the traditional distinction between metals and semi-metals is much less useful than a classification that distinguishes these 2 categories. Neglecting this distinction demonstrates a lack of understanding about which are the properties that determine the usefulness for practical applications of the chemical substances and a lack of understanding of how such properties vary with the atomic number.

Moreover, after one chooses some classification rules, those must be followed consistently. For example, anyone who chooses to call bismuth as a "metal" must also call carbon as a "metal", because the most stable state of carbon in normal conditions, i.e. graphite, has exactly as much reasons to be named as a "metal" or as a "post-transition metal" as bismuth has. There are a very large number of chemical compounds that are semi-metals, but among the pure elements carbon, antimony and bismuth are semi-metals (while boron, silicon, germanium, selenium and tellurium are semiconductors).

The reality is that too many authors of manuals just copy and paste automatically texts from other works without stopping to think whether they are correct and consistent.

[AnimalMuppet]

Nit: Things above helium are called metals. Helium is not.

Another nit: Astronomy, not astrology.

[Alghranokk]

Ah, that was quite an embarrasing error on my part, thanks.