which best describes an element in the periodic table An element in the periodic table is best described as a chemical element that has a unique atomic number and chemical properties. The periodic table is arranged in order of increasing atomic number, which corresponds to the number of protons in an atom’s nucleus. Elements with similar chemical properties are grouped together in columns, or groups, in the periodic table.
The first thing to know about the periodic table is that it is divided into columns and rows. The columns are called groups, while the rows are called periods. There are a total of 18 groups and 7 periods in the periodic table. The groups are further divided into two categories: main group elements and transition metals. Main group elements are those located in Groups 1-8, while transition metals are those located in Groups 3-12.

Elements in the same group have similar chemical properties because they have the same number of valence electrons. Valence electrons are the outermost electrons in an atom, and they are involved in chemical reactions. The number of valence electrons determines how reactive an element is.
The periods in the periodic table represent the increasing atomic number of the elements. As you move down a period, the atoms get larger and their nuclei get more massive. The elements in the first period (hydrogen and helium) are very light, while the elements in the seventh period (uranium and plutonium) are very heavy.
There are a total of 118 elements in the periodic table, but only 94 of them occur naturally on Earth. The other 24 elements are artificial, or man-made. The artificial elements were created in laboratories by bombarding atoms of other elements with high-energy particles.