Question

There are three parts to this question. Describe how each of these is used to organize the elements in the periodic table. This is not asking you to define these terms but to show how, if given the number, you would know where to look for that element in the periodic table.

The atomic number
The number of electron shells
The number of valence electrons

Answer 1

The atomic number determines the identity of an element, the number of electron shells corresponds to the energy level of an atom, and the number of valence electrons determines the chemical properties of an element.

Step-by-step explanation:

The atomic number of an element is the number of protons in the nucleus. It determines the identity of the element. Elements on the periodic table are listed in order of ascending atomic number, starting with hydrogen (atomic number 1). For example, if you were given the atomic number 8, you would know to look for the element oxygen.

The number of electron shells in an atom determines its energy level. The period or row that an element is in corresponds to the number of electron shells it has. For example, elements in the second row have two electron shells. If you were given the number of electron shells, you would know to look for the element in that row of the periodic table.

The number of valence electrons in an atom determines its reactivity and chemical properties. Valence electrons are the electrons in the outermost shell. The group or column that an element is in corresponds to its number of valence electrons. For example, elements in group 1 have one valence electron. If you were given the number of valence electrons, you would know to look for the element in that group of the periodic table.