Compare the properties of elements and compounds



Compare the properties of elements and compounds. Give two examples of each, including one example that exists in the human body. Explain the atomic nature of one element and one compound found in human body.

Elements are the most basic or purest forms of substances that exist. They cannot be broken down further into other substances. In other words elements are substances that are made up of just one kind of atom. Elements can occur in all three forms, solid, liquid, or gas. They can have various colors, shapes, and forms. They can be chemically reactive or inert. Compounds, on the other hand, are substances formed when two or more elements combine chemically. This combination takes place in fixed proportions of each of the building elements. The end result is the compound, whose physical and chemical properties may have no similarity to the properties of the elements from which it is made.

Two examples of elements are gold and calcium. Calcium is found in the human body, mainly in our bones and teeth. Two examples of compounds are hydrochloric acid and water. Water is found in the human body.

Calcium atoms are made up of 20 protons, 20 neutrons, and 20 electrons. The protons have positive charge, the electrons have negative charge, and the neutrons have no charge. The protons and neutrons are bundled in the nucleus of the atom. The electrons spin in orbits around the nucleus. It is classified as a metal, it is reactive, and is a good conductor of electricity.

Water is a molecule by structure. Each molecule of water is composed of two atoms of hydrogen and one atom of oxygen. In its solid form, ice, water is crystalline. The two hydrogen atoms each have one electron spinning around their nuclei. Each hydrogen nucleus contains one proton and no neutrons. The oxygen atom has two electrons spinning in an inner orbit and six electrons spinning in an outer orbit. When two hydrogen atoms and one oxygen atom combine to form water, the two electrons from the hydrogen atoms and six outer orbit electrons from the oxygen atom are shared by all three atoms. This makes a strong bond called covalent bond which makes it very difficult to separate the oxygen from the hydrogen in water.

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download