One last topic to cover before review: Dilutions

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One last topic to cover before review Dilutions
Some drugs are diluted prior to administration.
Simple calculation to use.
Voriginal x Coriginal Vfinal x Cfinal
Also referred to as
V1 C1 V2C2
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Dilution Problems
7.68 How many mL of 1.50 M NaOH are needed to
prepare 225 mL of 0.150 M NaOH?
7.65 A 10 (w/v) solution of ethanol is diluted
from 50 mL to 200 mL. What is the new
weight/volume ?
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Structures of Organic Compounds
H forms 1 bond O forms 2 bonds N forms 3 bonds C
forms 4 bonds
O and N have lone pair electrons C and H do not
have lone pair electrons
HONC
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Structures of Organic Compounds
H forms 1 bond O forms 2 bonds N forms 3 bonds C
forms 4 bonds
O and N have lone pair electrons C and H do not
have lone pair electrons
HONC
H forms 1 bond, not 2
O forms 2 bonds, not 3
C forms 4 bonds, not 3
Its not benzene, but its a valid structure
(cyclohexene)
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Line Bond and Skeletal Structures
Fluoxetine (Prozac)
Hydrogen atoms are drawn when attached to any
atom other than carbon
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Functional Groups
What functional groups are present in these
molecules?
Glycolic acid (alpha hydroxy acid)
Ethyl acetate (nail polish remover)
Phenylalanine (amino acid)
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Functional Groups
What functional groups are present in these
molecules?
Glycolic acid (alpha hydroxy acid)
Ethyl acetate (nail polish remover)
Phenylalanine (amino acid)
Carboxylic acid (RCOOH) Alcohol (ROH)
Ester (RCOOR)
Carboxylic acid (RCOOH) Aromatic (benzene) Also
amine (RNH2)
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Water Solubility or Lack Thereof
Water soluble?
Water soluble?
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Water Solubility or Lack Thereof
Water soluble?
Water soluble?
Cholesterol is not water soluble it is
transported by lipoproteins in blood (cholesterol
is lipophilic fat loving). Even though there
is an alcohol that can hydrogen bond the
MAJORITY of the molecule is non-polar.
Sucrose (table sugar) is water soluble. Can
hydrogen bond with water. MANY polar alcohol
groups (ROH).
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Differences in Electronegativity of Atoms Results
in Polar Bonds
F gt O gt N, Cl gt C, S, H
C-C, CC bonds are non-polar C-H bonds are
non-polar C-O, CO, C-N, N-H, O-H, C-Cl, C-F
bonds are polar
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Cis- and Trans- Isomers
Precursor in synthesis of drug Is this cis- or
trans- substituted?
Indinavir (Crixivan) Highly Active Antiretroviral
Therapy (HAART)
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Cis- and Trans- Isomers
Precursor in synthesis of drug Is this cis- or
trans- substituted?
Indinavir (Crixivan) Highly Active Antiretroviral
Therapy (HAART)
Cis
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Cis- and Trans- Isomers
2-butene
2-butene
Which is cis- and which is trans- isomer?
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Cis- and Trans- Isomers
trans-2-butene
cis-2-butene
cis-platin Chemotherapy drug
trans-platin No anti-tumor activity
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Non-Covalent Interactions
Intermolecular interactions not bonds!
Strength
Hydrogen bonds gt Dipole-dipole
interactions gt London forces
H-Bonds, dipole-dipole interactions, and London
forces are all weaker than covalent bonds
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Higher Boiling Point Correlated with Stronger
Intermolecular Forces (Non-Covalent Interactions)
Isopentane
Methyl ethyl ketone
Isobutanol
Assign the boiling points of 108 C, 80 C, 28 C
to the correct molecule. Explain why such
different boiling points.
Note - similar molecular weights (72-74 g/mol)
and surface areas.
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Higher Boiling Point Correlated with Stronger
Intermolecular Forces (Non-Covalent Interactions)
Isopentane
Methyl ethyl ketone
Isobutanol
London forces Boiling point 28 C
Dipole-dipole interactions Boiling point 80 C
Hydrogen bonding Boiling point 108 C
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Reactions

• Oxidation and Reduction
• Combustion oxidation of C (along with reduction
  of O)
• Hydrogenation reduction of C (along with
  oxidation of H)
• Hydrolysis Bond breaking by water (hydro
  water, lysis split)
• Condensation Bond formation with release of
  water (opposite of hydrolysis)
• Hydration Addition of water to a molecule
• Dehydration Loss of water from a molecule
  (opposite of hydration)

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Oxidation / Reduction Reaction Alcohol
Fermentation in Yeast
ethanol
acetaldehyde
Is acetaldehyde oxidized or reduced? Is NADH
oxidized or reduced? What is the reducing
reagent? What is the oxidizing reagent?
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Oxidation / Reduction Reaction Alcohol
Fermentation in Yeast
ethanol
acetaldehyde
Is acetaldehyde oxidized or reduced? Reduced
(gains H) Is NADH oxidized or reduced?
Oxidized (loses H) What is the reducing reagent?
NADH (it reduces acetaldehyde) What is the
oxidizing reagent? Acetaldehyde (it oxidizes
NADH)
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What Type of Reaction Is This?

• Oxidation/reduction
• Hydrolysis
• Condensation
• Hydration
• Dehydration

Lipase
Monoglyceride (monoacylglyceride) Alcohol
H2O
Two molecules oleic acid (cis- fatty
acid) Carboxylic acid
Triglyceride (triacylglyceride) Fat found in
olive oil
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What Type of Reaction Is This?
Hydrolysis
Lipase
Monoglyceride (monoacylglyceride) Alcohol
H2O
Two molecules oleic acid (cis- fatty
acid) Carboxylic acid
Triglyceride (triacylglyceride) Fat found in
olive oil
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What Type of Reaction Is This?

• Oxidation/reduction
• Hydrolysis
• Condensation
• Hydration
• Dehydration

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What Type of Reaction Is This?
Hydration
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What Type of Reaction Is This?

• Oxidation/reduction
• Hydrolysis
• Condensation
• Hydration
• Dehydration

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What Type of Reaction Is This?
Dehydration
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Reversible Reactions - Pushing the Reaction in
Either Direction
How can one increase ratio of cyclohexanol to
cyclohexene? How can one increase ratio of
cyclohexene to cyclohexanol?
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Reversible Reactions - Pushing the Reaction in
Either Direction
How can increase ratio of cyclohexanol to
cyclohexene? Add H2O How can one increase ratio
of cyclohexene to cyclohexanol? Remove H2O
The catalyst does not change the ratio of
cyclohexene to cyclohexanol
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Pushing a Reversible Reaction in Either
Direction
Carbon dioxide
Bicarbonate
Hydrogen ion
Carbonic acid
Which direction will reaction shift if CO2 is
added? Which direction will reaction shift if
CO2 is removed? Which direction will reaction
shift if H is added? Which direction will
reaction shift if H is removed?
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Pushing a Reversible Reaction in Either
Direction
Carbon dioxide
Bicarbonate
Hydrogen ion
Carbonic acid
Which direction will reaction shift if CO2 is
added? Which direction will reaction shift if
CO2 is removed? Which direction will reaction
shift if H is added? Which direction will
reaction shift if H is removed?
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Saturated, Unsaturated, or Polyunsaturated Fatty
Acids?
Palmitic acid - C16H32O2 Found in palm oil,
animal fats
Oleic acid - C18H34O2 Major component of olive
oil
a-Linolenic acid - C18H30O2 Omega-3 essential
fatty acid Flax seed, canola oil
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Saturated, Unsaturated, or Polyunsaturated Fatty
Acids?
Saturated fatty acid
Unsaturated fatty acid
Palmitic acid - C16H32O2 Found in palm oil,
animal fats
Oleic acid - C18H34O2 Major component of olive
oil
Polyunsaturated fatty acid
a-Linolenic acid - C18H30O2 Omega-3 essential
fatty acid Flax seed, canola oil
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Which Has a Higher Melting Point?
Stearic acid
Oleic acid
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Which Has a Higher Melting Point?
Stearic acid Melting point 70 C
Oleic acid Melting point 13 C
Stearic acid molecules pack more efficiently,
and thus a higher melting point.
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Solutions Homogenous Mixtures of Solvent and
Solute
Homogenous Evenly distributed Solvent
Component of solution that is present in greatest
amount Solute What is dissolved in solvent
Solubility is determined by non-covalent
interactions
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Water Soluble Vitamins and Fat Soluble Vitamins
Vitamin B5 (Pantothenic acid)
Vitamin A
Vitamin C
Vitamin E
Vitamin D
Solubility is determined by non-covalent
interactions
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Water Soluble Vitamins and Fat Soluble Vitamins
Vitamin B5 (Pantothenic acid) Water soluble
Vitamin A Fat soluble
Vitamin C Water soluble
Vitamin E Fat soluble
Vitamin D Fat soluble
Solubility is determined by non-covalent
interactions
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Concentration Calculations
Molarity moles/L (M)
Weight/volume (w/v ) g/mL x 100
Can also have volume/volume mL/mL x 100
weight/weight g/g x 100
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Equivalents (Eq) and Milliequivalents (mEq)
Equivalent is the number of moles of charge that
one mole of solute contributes to a solution.
How many equivalents is 1 mole of Na 1
mole of Ca2 1 mole PO43- 1 mole Cl-
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Equivalents (Eq) and Milliequivalents (mEq)
Equivalent is the number of moles of charge that
one mole of solute contributes to a solution.
How many equivalents is 1 mole of Na 1 Eq
Na 1 mole of Ca2 2 Eq Ca2 1 mole PO43- 3 Eq
PO43- 1 mole Cl- 1 Eq Cl-
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Questions from Chapter 7 Homework? Other
Questions?
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Solubility of Gases in Water
In contrast to most solids and liquids, in which
solubility increases at higher temperature, the
solubility of gases decreases with increasing
temperature.
and...
The solubility of gases increases with
increasing pressure.
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Consider SCUBA Diving
As a diver descends into deeper water, will more
or less gas be dissolved in his/her body?
If a diver swims into colder water, will more or
less gas be dissolved in his/her body?
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Pressure Increases with Depth of Diving Due to
the Weight of Water
Thus, as a diver descends into deeper water, more
gas will be dissolved in his/her blood. (Henrys
Law)
In addition, in colder water, more gas will be
dissolved in his/her blood.
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Decompression Sickness (The Bends) Can Occur When
a Diver Ascends too Quickly
As a diver ascends, the pressure decreases and
gases are less soluble. If a diver ascends too
quickly, the nitrogen gas comes out of solution
and forms bubbles.
Treatment hyperbaric chamber Re-dissolve gases
in blood, then slowly reduce pressure.
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Diffusion and Osmosis
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Semi-Permeable Membranes
Some membranes allow water to pass through, but
not other solutes Red blood cells Other
membranes allow water and small solutes to pass
through Cellophane membrane used in lab
Hemodialysis membrane
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Dialysis and Osmosis
Osmosis occurs when water moves through red
blood cell membranes to equalize the
concentration of solutes inside and outside the
cells Net movement of water from areas of lower
solute concentration to areas of higher solute
concentration (Areas of higher H2O concentration
to areas of lower H2O concentration) Dialysis
occurs when water and small solutes can pass
through a membrane (but not colloids or large
particles) Diffusion of solutes from areas of
higher concentration to lower concentration
occurs
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Osmosis is the Net Movement of Water Across a
Semi-Permeable Membrane From a Solution of Lower
Concentration Solute to a Solution of Higher
Concentration Solute
Membrane is only permeable to water - sugar can
not cross it. Thus, water will diffuse across
the membrane to approach closer to equal
concentration on both sides. This creates a
pressure difference - osmotic pressure.
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Hypotonic, Isotonic, and Hypertonic Solutions
Hypertonic Higher solute concentration than
inside cell Water moves out of cell gt0.9 NaCl
(saline) gt5 glucose (dextrose)
Hypotonic Lower solute concentration than inside
cell Water moves into cell lt0.9 NaCl
(saline) lt5 glucose (dextrose)
Isotonic Same solute concentration as inside
cell No net movement of water 0.9 NaCl
(saline) 5 glucose (dextrose)
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Effect of Isotonic, Hypertonic and Hypotonic
Solutions on Red Blood Cells (RBCs)
RBC in isotonic solution Same solute
concentration as inside cell No net movement of
water
RBC in hypertonic solution Higher solute
concentration than inside cell Water moves out
of cell
RBC in hypotonic solution Lower solute
concentration than inside cell Water moves into
cell
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Hemodialysis Removes Waste Products from
Metabolism via Diffusion Across Semi-Permeable
Membrane
Counter-current flow of dialysis solution versus
blood improve efficiency of diffusion
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Hemodialysis Removes Waste Products from
Metabolism via Diffusion Across Semi-Permeable
Membrane
Dialysis solution
Blood
Isotonic solution containing NaHCO3, NaCl KCl,
glucose, NaHCO3 Restore or maintain balance of
electrolytes and buffer
Blood cells and proteins too large to pass across
membrane
Waste products removed
creatinine
uric acid
urea