List the four major elements of the body and the major minerals and trace elements.
The elements carbon, oxygen, hydrogen, and nitrogen make up around 96% of body weight.
Some elements necessary for the body are referred to as minerals. The most important minerals
are calcium, chlorine, sulfur, potassium, sodium, magnesium, and phosphorus. Several other
elements are needed in small amounts, and are known as trace minerals:
chromium, copper, iodine, iron, manganese, selenium, and zinc. (See Table 24.3.)
Define the terms molecule, compound, mixture, solution, solvent, and solute and give
examples of each.
molecule - combination of two or more atoms held together by chemical bonds
When the two atoms are identical the resulting substance is called a molecule of that element (H
is a molecule of hydrogen gas).
compound – when two or more different kinds of atoms bind they form molecules of a
compound; chemically pure; all molecules identical (H
O is a compound – it is a molecule of