Ch.%202:%20Introductory%20Chemistry

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Ch. 2 Introductory Chemistry

• Chemical Compounds And Life Processes
• (Biochemistry)

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Objectives

• Identify and discuss the functions of water and
  inorganic acids, bases, and salts.
• Define pH and explain how the body attempts to
  keep pH within the limits of homeostasis

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Chemical Compounds And Life Processes
(Biochemistry)

• Inorganic molecules
• generally lack carbon
• held together by ionic or covalent bonds

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Chemical Compounds And Life Processes
(Biochemistry)

• Inorganic molecules (of our body)
• water
• acids and bases
• salts
• carbon dioxide (CO2)
• bicarbonate ion (HCO3-)

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Chemical Compounds And Life Processes
(Biochemistry)

• organic molecules
• always contain carbon
• usually contain hydrogen
• always have covalent bonds

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Chemical Compounds And Life Processes
(Biochemistry)

• organic molecules (of our body)
• carbohydrates
• lipids
• proteins
• nucleic acids (DNA,RNA)
• adenosine triphosphate (ATP)

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A. Inorganic molecules

• water
• chemical properties
• H20
• polar covalent bonds
• extensive hydrogen bonding

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Inorganic molecules

• water
• properties making it a vital compound
• Polar solvent properties
• Water is an excellent solvent
• - this is due to its polar covalent bonding and
  its bent shape
• a. solute -
• solvent -
• solution -

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Inorganic molecules

• water
• properties making it a vital compound
• Reactivity
• Water is an important reactant (in chemical
  reactions)
• Involving hydrolysis reactions
• - important for dissolving and enabling
  absorption of dietary nutrients in the body

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Inorganic molecules

• water
• properties making it a vital compound
• High heat capacity
• Water has slow absorption and slow release of
  heat rates
• moderates the effect of changes in environmental
  temperature
• - important to maintain homeostasis of body
  temperature

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Inorganic molecules

• water
• properties making it a vital compound
• High level of vaporization
• Water requires a large amount of heat to change
  from liquid to gas
• - important in providing excellent cooling
  mechanism

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Inorganic molecules

• water
• properties making it a vital compound
• Protection / Cushioning
• serves as a lubricant and protectant
• - example(s)

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Inorganic molecules

• salts
• ionic compounds dissolve into their ions when
  dissolved in body fluids (dissociation breaks
  apart)
• all salts (ions) are considered electrolytes when
  dissolved in water

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Inorganic molecules

• acids and bases
• acid (proton donor)
• when dissolved in water, they release hydrogen
  ions (H) (protons) and some anions (ionize)
• strong acids ionize completely and liberate all
  their protons i.e.) hydrochloric acid (HCl)
• weak acids ionize incompletely
• i.e.) carbonic acid (H2CO3)

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Inorganic molecules

• The acid in your stomach is strong enough to
  dissolve razor blades

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Inorganic molecules

• base (proton acceptor)
• dissociate in water but release hydroxyl ion
  (OH-) and some cations
• strong base i.e.) sodium hydroxide (NaOH) (lye)
• weak base i.e.) sodium bicarbonate (NaHCO3)

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pH scale

• pH units 0 to 14 7 is neutral
• a change of 1pH unit is a 10-fold change in
  hydrogen-ion concentration
• pH lt 7 - acidity (acidic)
• pH gt 7 - alkaline (basic)
• living cells are highly sensitive to slight
  changes in pH
• homeostasis of acid-base balance is regulated by
  the kidneys, respiration, and chemicals called
  buffers in the blood i.e.) NaHCO3

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???Questions???

1. Give four reasons continual water intake is
   essential to life.

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???Questions???

• Salts, acids, and bases are electrolytes. What
  is an electrolyte?
• 26. Compare and contrast acids and
• bases.
• Define pH.

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???Questions???

• State which of the following would be acidic,
  which basic, and which neutral
• pure (distilled) water -
• vinegar
• sodium bicarbonate
• gastric juice -

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???Questions???

• The pH range of blood is from 7.35 to 7.45. This
  is slightly acidic or basic?
• A pH of 3.3 is ____________ (1, 10, 100, 1000)
  times more acidic than a pH of 4.3.