First some background...
An element is anything with only one type of atom.
In terms of Chemical structure, any time you see more than one capital letter (like H2O) that automatically it has more than one element, or more than one kind of atom.
So some examples:
H2O (Water)
NaCl (Salt)
C3H8 (Propane)
SiO2 (Sand)
C12H22O11 (Sugar)
A couple of examples would be salt water and sugar water. The salt and sugar dissolve in the water, but still exist as smaller molecules (or in salt's case, as sodium and chlorine ions) among the water molecules.
Epsom salt is a compound. It is composed of the elements magnesium, sulfur, and oxygen bonded together in a specific ratio. It is not a pure substance like an element, but rather a combination of different elements.
A compound is a substance composed of two or more elements chemically bonded together. It has a unique chemical structure and properties different from its constituent elements. Examples include water (H2O) and salt (NaCl).
A compound is a substance formed when two or more elements are chemically joined. Water, salt, and sugar are examples of compounds. Most pure substances are compounds A compound is a substance formed when two or more elements are chemically joined. Water, salt, and sugar are examples of compounds. Most pure substances are compoundsA compound is something that has two or more atoms bound together. An example would be water, glucose, alcohol, vinegar.
Usual table salt requires two chemical elements to exists (Na+, Cl-).
A substance containing atoms of two or more elements combined together is called a compound. Compounds have a fixed ratio of elements and typically have different properties from the elements they are composed of. Examples include water (H2O) and table salt (NaCl).
A compound is a substance consisting of two or more elements. Table salt, NaCl, includes the elements of Sodium (Na) and Chlorine (Cl). Therefore, it consists of two elements, making it a compound.
A compound is a substance consisting of two or more elements. Table salt, NaCl, includes the elements of Sodium (Na) and Chlorine (Cl). Therefore, it consists of two elements, making it a compound.
Sodium Chloride, (NaCl).
A pure element is a substance made up of only one type of atom, such as oxygen or gold. A compound is a substance made up of two or more different elements chemically bonded together, like water (H2O) or salt (NaCl).
Pure substance can be identified as either elements or compounds. Some examples of pure substance that are elements are sulfur and tin. Pure substances that are compounds are sugar and salt.
Salt is a pure substance, i.e. it is an ionic compound consisting of two elements sodium and Chlorine. The formula is NaCl.
Table salt is sodium chloride made from the elements Sodium (Na) and Chlorine (Cl).
Table salt, sodium chloride, is both a compound and a substance. You should understand that the word substance is a very general term. Elements, compounds, or mixtures, all qualify as substances. All matter is made up of substances of some kind. Whereas a compound is a specific kind of substance, one that is composed of the chemical combination of two or more elements.
Heat is energy, not a substance. When reactive elements combine they form more stable compounds. The exact substance formed depends on the elements. e.g. hydrogen and oxygen form water while sodium and chlorine form common table salt.
Table salt (sodium chloride) is an example of a compound. It is made of two elements, sodium and chlorine, combined in a fixed ratio.
Air cannot be classified as a substance because it is a mixture of various gases like nitrogen, oxygen, and carbon dioxide. Substances, on the other hand, are pure materials composed of one type of atom or molecule.