Introduction to bonding By Joe Lutz

 All elements in nature occur in chemical combination or bonding  Only a few elements known as the Noble Gases don’t participate in bonding  These elements are Helium, Neon, Argon, Krypton, Xenon and Radon

 Bonding can happen two ways…  The first way is known as ionic  Ionic bonding uses the transfer of electrons to bond elements  This type of bonding usually involves a metal and a nonmetal if the bond is a binary ionic compound(composed of two elements)  In binary ionic compounds, metals lose a certain amount of electrons and become cations(+ charged ions) while nonmetals gain those electrons becoming anions(- charged ions)  However, Ionic compounds have no net charge  All binary ionic compounds are solids!!!!!

Elements either give or receive electrons to reach stability. Based on their electron configurations and their charges will determine whether they give or receive electrons.

 The second type of bond is a covalent bond, which uses the sharing of electrons to help each element reach stability  Covalent bonds usually happen between nonmetals  Covalent bonds can be polar depending on if the electrons are pulled to one element rather than the other

 The key distinction between covalent and ionic bonds is how the elements are bound together  In an ionic bond the elements are bound together by oppositely charged ions  In a covalent bond the elements are bound together by shared electrons

 Only about a quarter of all the elements in the world have a known duty in the life of organisms  There are four elements known as the “building block elements” and these are Carbon, Oxygen, Hydrogen and Nitrogen  Also, there are seven major minerals or macronutrients that are pretty common  There is also some trace elements that are take up very low percentages of organisms and do specific roles

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