What is a non example of element, compound, and pure substance

Hmmm... Water? It's not an element. it's made of two so it's bi and not compound. It's not pure because it disperse and evaporates under heat. Pure substances are more like metals

• Element non examples include all compounds, which are substances made when two different types of atoms form a chemical bond. Any material made by mixing elements is no longer an element. Anytime you see a chemical formula with more than one element symbol in it, it’s an element non example.

• The most popular non examples of a compound are gold, silver , and bronze.

•A pure element or compound contains only one substance, with no other substances mixed in. Inpure materials may be mixtures of elements, mixtures of compounds, or mixtures of elements and compounds.

Ithink about 50 % of an original isotope's number of atoms remain

The mole ratio of hydrogen to ammonia is 3: 2.