Question

Is tellurium a metalloid?

Answer 1

See below

Explanation:

Tellurium will almost always be considered a metalloid, yes, due to its chemical properties that lead it to be classified as such.

In fact, I came across this Wikipedia page a little while back that shows a complete list of sources that consider select elements "metalloids". (Check it out, it's pretty interesting.)

You'll find that six are most commonly considered metalloids (in descending order of most classifications, `"As"`, `"Te"`, `"Ge"`, `"Si"`, `"Sb"`, `"B"`). Notice tellurium is the second most "agreeable metalloid", if you will, at `98%`.

Another interesting detail about this source is that no element is regarded as a metalloid by all of the sources...

All in all, the classification ultimately depends on context and the desired classification. That is to say, in some respects a certain element behaves more like a metalloid, but not as much when regarding a different property.