Intro to BioChem: Basic Chemistry Concepts (Ch. 2)

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Intro to BioChem Basic Chemistry Concepts (Ch. 2)
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Definitions

• Element
• -A substance that cant be broken down into
  simpler chemical substances.
• Atom
• -The smallest part of an element that upholds the
  chemical properties of that element
• -Whats smaller an atom or element?

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Structure of an Atom

• Atoms have a nucleuslocated in the center of the
  atom
• Atoms have electron energy levelssurround the
  nucleus

ATOM
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Structure of an Atom

• Three subatomic particles
• The nucleus is composed of 2 particles.
• Protons positively charged
• - shown in diagrams as
• p or
• Neutrons particles with no charge
• - shown in diagrams as
• no or o
• (The nucleus is positively charged.)

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• Electrons form clouds around the nucleus.
• Negatively charged particles
• Move rapidly randomly around the nucleus
• Shown in diagrams as e- or -

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• How do we calculate how many protons, neutrons,
  and electrons an atom has?
• 1. Atomic Number of protons.
• 2. Assume of protons of electrons.
• 3. of neutrons atomic mass - of protons.

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How many electrons can a energy level hold?

• First energy level
• Closest to the nucleus
• Smallest
• Holds up to 2 electrons
• Second energy level
• Next one out after first energy level
• Bigger Holds up to 8 electrons
• Third energy level
• Next one out after 2nd energy level
• Larger yet holds up to 8 electrons

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• Atoms can contain equal numbers of electrons and
  protons. (e p)
• If an atom loses an electron, it becomes
  positively charged
• If an atom gains an electron, it becomes
  negatively charged