Technetium is found in both in a compound and pure forms
No, they are rarely found in elemental form.
Helium has completely filled orbitals. hence it is chemically inert (non reactive) and is found in its pure elemental form.
technetium forms with other elements to make compounds
Yes in the sense that you can have a compound and add a chemical or element to it in order to remove an atom from the compound, thus returning it to its elemental form. For example, KI + Li --> LiI + K. The Potassium (K) was in a compound but is now alone in its elemental form after the reaction. (Lithium can replace Potassium because it is more reactive. See the Activity Series for more info on that).
STABLE all the way!
It is a compound
Calcium is never found in its elemental form in nature.
Chlorine is not found in the nature in his elemental form.
Yes. helium is found only in elemental form
No, they are rarely found in elemental form.
In nature, titanium is always found as a compound, not as a pure metal. Titanium is highly reactive (although less reactive alloys can be made from it).
It would not be a compound. It is simply fluorine in its elemental form.
Sodium is an extremely reactive element, meaning that it is unstable in its elemental form and stable in compounds. It will react spontaneously with oxygen, water, carbon dioxide, and even nitrogen. As a result, it does not naturally occur in elemental form.
Yes. helium is found in its elemental form. it is chemically inert as it has completely filled orbitals.
No. Ammonia is a compound. An allotrope is a substance in its elemental form.
No. Almost all technetium is man made. In nature it is found only in trace amounts mixed in uranium or platinum ores.
Technetium can form oxides, chlorides, bromides, fluorides, sulfides, selenides, tellurides, carbides, pertechnetates etc.