Chemistry of Life October 18 & 19, 2012

Chemical ElementsC.H.O.N.P.S.

• In the Atmosphere: Nitrogen (78.1%), Oxygen (20.9%)

• In the Human Body: Oxygen (65%), Carbon (19%), Hydrogen (10%), Nitrogen (3%), Phosphorus (1.2%), Sulfur (0.2%)

Chemistry of Life October 18 & 19, 2012

Carbon Found in ALL organic compounds

Organic Compounds – Carbon containing compounds produced by living things, except Hydrogencarbonates (HCO3

-), Carbonates (CO32-), and Oxides of Carbon

(CO- & CO2)

Symbol “C” forms 4 covalent bonds with other atoms

Ionic Bonds involve elements from opposite sides of the periodic table, where one element is positively charged and the other is negatively charged… these charged particles are called Ions.

Chemistry of Life October 18 & 19, 2012

Hydrogen Most Abundant Element in this

Universe Symbol “H” forms 1 covalent bond with

another atom Forms Hydrogen Bonds

Hydrogen Bonds – very weak bonds, much weaker than ionic and covalent bonds; force of attraction between a slightly positive Hydrogen (Hδ+) and a slightly negative Oxygen (Oδ-)

Chemistry of Life October 18 & 19, 2012

Oxygen Most abundant element found in

Human Body Symbol “O” forms 2 bonds with

other atoms

Commonly found in its gaseous form O2

Chemistry of Life October 18 & 19, 2012

Nitrogen Most abundant element in the Earth’s

atmosphere Symbol “N” forms 3 covalent bonds with other

elements

Nitrogen is a major component of Proteins (found in

the amino group of Amino Acids) and Nucleic Acids (in the Nitrogenous Bases – Adenine, Guanine, Cytosine, Thymine, and Uracil)