Pure substances can or can not be chemically combined.
Pure substances can be either elements or compounds, but not mixture. Mixture are different substances mixing together without being chemically combined, such as air, which is a mixture of oxygen, carbon dioxide, water etc. Mixture can be separated by physical methods, like filtration or decantation.
Meanwhile, elements are the substances that cannot be further separated by any means. No matter physical or chemical methods. Examples of elements are oxygen, hydrogen, neon and all the other ones from the periodic table. Compounds are basically elements joining together, but they’re chemically combined which means their electrons (kind of subatomic particle) are either shared or given away. These elements can only be separated by chemical methods like electrolysis or heating.
Therefore, as long as the substance cannot be separated by physical methods, it can be considered as a pure substance. We can now conclude that pure substance can be (element) or can not be (compound) chemically combined.
That’s because when a charged chemical species composes of two or more atoms (covalently bonded), they act as a single unit. the term radicals refers to free radicals that are with an unpaired electron and because not all of its electrons are found in pairs
Answer: One of the most common iron oxides is iron (III) oxide, known as rust. The chemical formula for rust is Fe2O3. Rust is formed when iron reacts with oxygen in moist air. The following chemical equation represents the reaction: 4Fe + 3O2 → 2Fe
Answer:
the relative molecular mass of hydrated iron (II) sulfate FeSO4.7H2O is 278.02
Explanation:
