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Chemistry in Biochemistry
• To know biochemistry, you do have to know some basic chemistry.
• Hence the “chemistry” in biochemistry.
The Atom in Biochemistry
• In Biochemistry, the protons and neutrons are not really that important.
• The number of protons in an atom, for a specific element will always remain constant.
• Number of protons= Atomic Number• Using this property, you can identify the element.• Number of Neutrons + Protons= Atomic mass
Electrons
• A neutral atom has the same number of electrons as protons
• The electrons orbit around the nucleus in paths called orbitals or shells
• The outermost shell is known as the valence shell
• Electrons that inhabit that shell are known as valence electrons.
• The adjacent diagram is a Louis Dot Diagram, which can be used to show the number of valence electrons.
Different kinds of bonds
• 3 different kinds of bonds
• Ionic Bond (Give or take electrons)
• Covalent Bond (sharing of electrons)
• Hydrogen Bond (not really a bond!)
Ionic Bonds
• All atoms have valence electrons
• All atoms want to get to either 0 valence electrons in the outer shell, or eight
• This is known as the Octet rule• Certain elements-their atoms
want to gain electrons (these are known as nonmetals)
• Other elements-their atoms want to lose electrons (these are known as metals)
• If electrons gain or lose electrons, they become something known as ions.
Ionic Bonds (Cont.)
• Using the periodic table, you can figure out which atoms want to lose or gain
• The number of electrons the atom needs to lose or gain is known as the oxidation number
• So for ionic bonding to occur, you need to fill one atom’s shell up, and empty others.
• The nonmetal will normally gain the electrons, unless it’s a bond between two nonmetals.
• In this, electronegativity will decide who loses or gains.
• Now, say an atom wants to lose 2 electrons, and another atom wants to gain two electrons, then atom 1 will lose its electrons, and atom 2 will get the electrons. This makes them bond.
• Likewise, if you’ve got an atom that loses 1 electron, and another atom that desires to gain 2, then two atoms of atom 1 and 1 atom of atom 2 will bond.
• Like math, so (+1 + +1) + (-2) = 0
Covalent Bonds
• In this type of bond, atoms share electrons
• Neither atom has strong enough force to steal the others electrons so they share the electrons
• The shared electrons then orbit around both of the atoms, causing one atom to be sometimes more electrically negative than the other
• Ex of a naturally occurring covalent bond is water
Hydrogen Bonds
• Hydrogen bonds are not really bonds
• They are just a weak electromagnetic attraction between the ends of the hydrogen bonds to the oxygens
• Hydrogens are slightly less polar than the oxygens, so they are attracted to each other
Citations for Photographs
• "Images." What Is Diabetes? Caused by Toxic Oils, Cured by Natural Ones. Web. 02 Dec. 2010. <http://www.hidden-diabetes-cures.com>.
• DynamicDrive.com, By. "Images." Faculty & Staff :: Georgia Perimeter College. Web. 02 Dec. 2010. <http://facstaff.gpc.edu >.
• "Images." Home Page. Web. 02 Dec. 2010. <http://chemcool.com/>.
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