Atoms, Elements and The Periodic Table

Atoms, Elements and The Periodic Table

1. Elements

   • They basic building blocks of matter
   • Cannot be broken into simpler chemicals
   • all atoms of an element are the same
   • atomic structure of an element determine the position of the element in the periodic table

2. Atomic Structure

   • Each atom contains a small positively charged nucleus
   • nucleus is made up of two types of particles
     • Protons -Positively Charged
     • Neutrons- NO charge
   • negatively charged ELECTRONS orbit the necleus
   • every atom of the same element has the same amount of protons
     • The Number of PROTONS is known as the atomic number
   • The mass of the atoms is known as the RELATIVE ATOMIC NUMBER

3. The Periodic Table

   • Medeleev
     • first periodic table was created by dmitri medeleev in 1869
     • he noticed patterns when the elements were arranged in order of relative atomic mass
     • there was gaps in the sequence that represented unknown elements
   • Arranged in a logical way which allows you to predict the properties of other elements E.g In order of Atomic mass
   • the rows are called periods
   • the columns are called Groups
   • some elements in the middle are called - the transition metals and have no group number