Unit 2: The Chemistry of Life

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Unit 2 The Chemistry of Life

• 1. Basic Chemistry
• 2. Water
• 3. Acids and Bases
• 4. Carbon
• 5. Biomolecules

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I. The Nature of Matter
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II. The Composition of Matter

• Atom the basic unit of matter
• subatomic particles
• proton
• neutron
• electron

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The Periodic Table

• Symbols for elements. life elements
• Atomic Number represents the number of
  protons/identifies the atom ( of p)
• Atomic Mass represents the number of protons and
  neutrons ( of p of n)
• atomic mass - atomic number neutrons

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• Neutral Atom of p of e-
• Ion an atom that has gained or lost an electron
  ( ion or ion)
• Isotope atoms of an element which have different
  atomic masses than other atoms of the same
  element
• gained or lost neutrons

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Elements

• Basic substance that makes up the material world
  - composed of only one type of atom
• Know the symbols for the major life elements.

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Radioactive Isotopes

• Unstable nuclei (break down) release matter E
  radiation
• Uses to study living organisms, sterilize foods,
  diagnose treat diseases, measure the age of
  rocks fossils, chemical tracers

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• Compounds substances consisting of 2 or more
  different atoms (most material in the living
  world.)
• Molecules a group of atoms held together by
  covalent bonds
• Chemical Formulas shorthand using the symbols
  for the elements and s representing their
  proportion

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III. Interactions of Matter

• Energy (E) power needed to carry on life
  activities
• The E used by living things is chemical potential
  E
• Electrons
• Energy Levels in Atoms a series of orbits in
  which electrons travel around the nucleus of an
  atom (each energy level holds a certain of
  electrons)

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The Octet Rule (Biology Version)
Atoms react with one another to achieve 8
electrons in their outermost shells except when
1st E-level is the outer shell 2 electrons
2 - 8 - 8
Stable atoms have full outer orbitals.
Nucleus
Most atoms will form chemical bonds with other
atoms to become stable. Chemical Reactions
Energy Levels max. e-
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Chemical Reactions

• Any process in which a chemical change occurs

C6H12O6 6 O2 6CO2
6H2O Reactants Products

• Chemical Equations are the shorthand way to
  describe a chemical reaction. (balanced)