The periodic table starts from hydrogen with atomic number "1". All periods begin with an alkali metal in group 1 and end with a noble gas in group 18/8A. #"Groups"#, which reflects the number of valence electrons, and then placed in rows, in #"Periods"#, which is a measure of the distance of the #"valence electrons"# (i.e the outermost electrons) from the nuclear core. It is in ascending order (less to more). The periodic table may look complicated, but much of it comes down to one simple pattern: the transition from metal to nonmetal elements. The different colours in the periodic table are further classifications of the elements … They are placed with the lowest atomic number first, and elements with increasing atomic numbers run to the right. The atomic number is the number found at the top of each box on the periodic table. Periodic table is the amazing and magical rearrangement of elements. The elements are arranged into 18 groups (columns) and seven periods (rows) by increasing atomic number. The periodic table is one of the most valuable tools for chemists and other scientists because it orders the chemical elements in a useful way. Elements are arranged in the order of increasing atomic number (number of protons in the nucleus of an atom of an element). Once you understand how the modern periodic table is organized, you'll be able to do much more than just look up element facts like their atomic numbers and symbols. The Periodic Table DIRECTLY reflects the electronic structure of a given element. They are also arranged in vertical columns known as groups, with these groupings based on shared properties. In the modern periodic table, elements are arranged by atomic number. Elements are arranged on the periodic table in the order of the atomic number, in groups and periods. Elements are arranged from left to right and top to bottom in order of increasing atomic number. Each horizontal line of elements on the modern periodic table is known as a period. Elements are arranged in order of increasing atomic number. The periodic table of elements arranges all of the known chemical elements in an informative array. They are arranged according to their atomic number, i.e., the number of protons or electrons in their atoms. Each element has its own unique atomic number, which is the number of protons in the nuclei of its atoms, and which defines the element. Elements are placed in columns, i.e.