The Periodic Table

• All the elements in the periodic table are listed in order of their atomic number.  
• The atomic number never has a decimal. 
• Elements are categorized in groups. 
• The atomic number is always the smaller number. 
• Groups go vertically and periods are horizontal across the Periodic Table 
• The atomic number shows the amount of protons in the table 
• Dmirti Mendeleev created the periodic table. 
• Russian chemist Dmitri Mendeleev organised the elements by their atomic weight. 
• However he swapped some elements so the chemical properties matched better