Basic Chemistry

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Basic Chemistry

• Chapter 2
• Lecture Notes

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Matter and Energy

• Matter anything that occupies space and has
  mass (weight) the stuff of the universe
• 3 states of matter
• Solid
• Liquid
• Gas

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Matter and Energy

• Energy the ability to do work putting matter
  into motion massless
• 4 forms of energy
• Chemical
• Electrical
• Mechanical
• Radiant

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Composition of Matter

• Elements fundamental units of matter
• Periodic table lists all 112 elements, their 1
  or 2 letter symbols, atomic number, and atomic
  weights
• 4 elements compose approximately 96 of the human
  body
• Carbon (C)
• Oxygen (O)
• Hydrogen (H)
• Nitrogen (N)

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Atomic Structure

• Atoms building blocks of elements
• Nucleus center of every atom an contains
• Protons (p) positive charge
• Neutrons (n0) no charge
• Outside of the nucleus contains
• Electrons (e-) negative charge

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Atomic Structure
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Identifying Elements

• Atomic Number equal to the number of protons
  that the atom contains
• Atomic Mass the sum of the protons and the
  neutrons

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Molecules and Compounds

• Molecule 2 or more LIKE atoms combined
  chemically
• Example H (atom) H (atom) H2
• Compound 2 or more DIFFERENT atoms combined
  chemically
• Example 4H C CH4 (methane)

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Chemical Bonds and Reactions

• Chemical Reactions occur whenever atoms combine
  with, or dissociate from, other atoms
• Atoms are united by chemical bonds
• Electrons occupy energy levels called electron
  shells
• Electrons closest to the nucleus are most
  strongly attracted

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Chemical Bonds and Reactions

• Each electron shell has distinct properties
• Number of electrons has an upper limit
• Shells closest to nucleus fill first
• Shell 1 can hold 2 electrons
• Shell 2 can hold 8 electrons
• Shell 3 can hold 18 electrons

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Chemical Bonds and Reactions

• Valence Shell outermost shell that contains
  electrons
• Bonding involves interactions between electrons
  in the valence shell
• Full valence shells do not form bonds
• Inert Elements have complete valence shells and
  are stable
• Rule of 8s atoms interact so that they will
  have 8 electrons in their valence shell

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Types of Chemical Bonds

• Ionic Bonds form when electrons are completely
  transferred from one atom to another
• Na Cl NaCl
• Ions are charged particles they either donate
  or accept electrons
• Anions negative ions
• Cations positive ions

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Types of Chemical Bonds

• Covalent Bonds shared electron bonding
• Single covalent bonds share one electron
• H H H2
• Double covalent bonds share two electrons
• O O O2
• Hydrogen Bonds weak covalent bond where H is
  attracted to negative portion of a polar molecule

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Examples of Covalent Bonds
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Types of Chemical Reactions

• Synthesis Reaction atoms or molecules combine
  and energy is absorbed for bond formation
• A B AB
• Decomposition molecule is broken down and
  energy is released
• AB A B

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Examples of Chemical Reactions
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Types of Chemical Reactions

• Exchange Reactions involves both synthesis and
  decomposition reactions. A switch is made
  between molecule parts and different molecules
  are made.
• AB CD AD CB

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Biochemistry Essentials for Life

• Two major classes of molecules
• Organic Compounds contain carbon and most are
  covalently bonded
• Inorganic Compounds lack carbon and tend to be
  simpler compounds

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Organic Compounds

• Carbohydrates contain C, H, and O and include
  sugars and starches are classified according to
  their size
• Monosaccharides simple sugars
• Glucose
• Disaccharides 2 simple sugars joined by
  dehydration synthesis or hydrolysis
• Sucrose glucose fructose
• Polysaccharides long branching chains of linked
  simple sugars
• Starch
• glycogen

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Examples of Sugars
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Examples of Sugars
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Organic Compounds

• Lipids contain C, H, and O C and H outnumber
  O are insoluble in water
• Triglycerides (neutral fats) found in fat
  deposits and are composed of fatty acids and
  glycerol source of stored energy
• Phospholipids form cell membrane
• Steroids include cholesterol, vitamin D, and
  some hormones

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Organic Compounds

• Proteins contain C, O, H, N and sometimes S
  made up of amino acids
• Account for over half of the bodys organic
  matter
• Provides for construction materials for body
  tissues
• Plays a vital role in cell function
• Act as enzymes, hormones, and antibodies
• Enzymes act as biological catalysts which
  increase the rate of chemical reactions

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Organic Compounds

• Nucleic Acids provide the blueprint for life
  make DNA and RNA and are composed of nucleotide
  bases
• Adenine
• Guanine
• Cytosine
• Thymine found only in DNA
• Uracil found only in RNA
• DNA DeOxyRiboNucleic Acid provides
  instruction for every protein in the body
• RNA RiboNucleic Acid

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DNA
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Organic Compounds

• Adenosine TriPhosphate (ATP) chemical energy
  used by all cells energy is released by breaking
  high energy phosphate bonds and producing ADP

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Inorganic Compounds

• H2O (water) most abundant inorganic compound
• Salts easily dissociate into ions in the
  presence of water and they are vital to many body
  functions include the electrolytes which conduct
  electrical currents

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Inorganic Compounds

• Acids are proton donators can release
  detectable H ions have a sour taste and can
  dissolve many metals or burn holes in materials
• Bases are proton acceptors have a bitter taste
  and feel slippery
• Neutralization Reaction acids and bases react
  to form water and a salt

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pH Measurements

• pH measures relative concentrations of H ions
• pH 7 neutral
• pH lt 7 acidic
• pH gt 7 basic
• Buffers chemicals that can help regulate pH
  change

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