Exam 1- Dr. A's Stuff

Question 1

Molarity

Answer 1

M

moles of solute/ 1 L of solution

Question 2

Molality

Answer 2

m

moles of solute / 1000g (1kg) of solvent

Question 3

Mole Fraction

Answer 3

ratio of moles of one constituent to total moles

X = moles of solute/ (moles of solute + moles of solvent)

X must = 1

Question 4

Percent by weight

Answer 4

% w/w

grams of solute / 100g of solution

Question 5

Percent by volume

Answer 5

% v/v

mL of solute / 100mL of solution

Question 6

Percent weight-in-volume

Answer 6

% w/v

grams of solute/ 100mL of solution

Question 7

Density

Answer 7

grams of solution /1 mL of solution

density = mass/volume

p=m/v

g/cm³

(1 mL = 1g = 1cm³)

Question 8

ad

Answer 8

up to

-or-

quantity sufficient

Question 9

TPN

Answer 9

Total parenteral nutrition

Question 10

Why is age frequently considered in determining the proper dosage?

Answer 10

Because renal function develops over the first 2 years of life. Thus newborns are very sensitive to certain drugs.

Question 11

BSA

Answer 11

• The body surface area (BSA) method of calculating drug doses is widely used in pediatric patients (except newborns) and cancer patients receiving chemotherapy.
• For precise calculations based on both height and weight, we can refer to a standard nomogram.
• The BSA in square meters (m²) is indicated where a straight line drawn to connect the height and weight of the child intersects the surface area column.

Question 12

Child’s BSA Equation

Answer 12

(BSA of child in m² )/(1.73m²) X adult dose = child’s dose

1.73m² =average adult BSA

Question 13

Drug definition

Answer 13

A drug is defined as an agent intended for use in the diagnosis, mitigation, treatment, cure, or prevention of disease in humans or in other animals.

Question 14

The only difference between a drug and a poison is?

Answer 14

The dose

Question 15

Drugs usually require…

Answer 15

• Stability (make it in bulk, want 2 year shelf life)
• Components must be physically and chemically compatible
• Protected from microbial contamination, heat, light, moisture, etc.
• Therapeutic ingredients must be released in proper amount at proper time
• Attractive flavor, color, texture (helps patient compliance, especially with kids)

Question 16

Drugs date back to?

Answer 16

Approximately 3000 BC

Question 17

Disease was often believed to be caused by?

Answer 17

The entrance of demons or evil spirits into the body

• In the early apothecaries, it was believed that a drug had magical associations.
• This meant that its action, bad or good, did not depend on its qualities alone; a compassionate god, the absence of evil spirits, and the healing intent of the dispenser were important.
• Because of this, the tribal apothecary was one to be feared, respected, and revered due to the need for spiritual intervention.
• With time, the art of apothecary combined with priestly functions, and the priest-magician became the healer of the body as well as the soul.

Question 18

What is the most famous ancient writing on drugs?

Answer 18

The Ebers Papyrus that is 60 feet long and has more than 800 formulas and 700 drugs dating back to 1550 BC

Question 19

What delivery vehicles were used back in the day?

Answer 19

Commonly beer, wine, milk, honey

Question 20

Hippocrates

Answer 20

• 460-377 BC
• Described hundreds of drugs
• The term “pharmakon” came to mean a purifying remedy for good only.
• This was different from the previous belief that a charm or drug could be used for evil or good

Question 21

4 humors

Answer 21

Any sickness was due to an imbalance in the 4 humors, the 4 fluids in the body

• Black bile
• Yellow bile
• Blood
• Phlegm

Question 22

Dioscorides

Answer 22

• 1st century
• Studied pharmaceutical botany and described collection and proper storage.
• Also had means of detecting contaminants, and set standards.

Question 23

Galen

Answer 23

• 130-200 AD
• Wrote about numerous drugs and described preparations of vegetable drugs by mixing and compounding.
• The field of pharmacy was once commonly referred to as “Galenic Pharmacy”.

Question 24

Avicenna

Answer 24

• 981-1037
• Wrote the Canon of Medicine in Persia that remained a common medical text in Europe until the 18th century.
• The text stated that disease could be spread through water, soil or air.
• Introduced the ideas of quarantine (to limit disease), evidence-based medicine, and randomized clinical trials.

Question 25

Pharmacy was officially separated from medicine in?

Answer 25

1240 by Emperor Frederick II of Germany

Question 26

Pharmacists were required to prepare?

Answer 26

Reliable drugs of uniform quality. ## Footnote Side note: Any exploitation of the patient through business relations between the pharmacist and the physician were forbidden.

Question 27

Aureolus Theophrastus Bombastus von Hohenheim

Answer 27

Aka. Paracelsus * 1493-1541 * Transformed the profession from one based on botany to one based on chemistry. * He believed it was possible to cure any disease with a specific medicinal agent.

Question 28

The Pharmacopeia of London was published in?

Answer 28

* 1618 * It contained descriptions of how to mix components and contained standards.

Question 29

1698

Answer 29

The first patent- epsom salts

Question 30

When was morphine isolated from opium?

Answer 30

* 1805 * Was developed as a pain killer; a "miracle drug". * It eliminated pain and produced a dream like state, so named 'Morphine" after Morpheus, the Greek God of dreams

Question 31

Quinine, caffeine, codeine...

Answer 31

* Isolated in the early 1800s. * The extraction and isolation of active constituents led to the development of dosage forms of uniform strength.

Question 32

United States Pharmacopeia (USP) was first published in?

Answer 32

* 1820 * Published in English and Latin * Pharmakon (drug) was combined with "poiein" (make). This provided standards to insure drug quality. * 272 pages and 217 drugs considered worthy of recognition. * This document reflected the fact that the apothecary was competent at collecting and identifying botanical drugs, and preparing mixtures required by the physician.

Question 33

First pharmacy school in the nation?

Answer 33

* The Philadelphia College of Pharmacy * 1821

Question 34

What was the first organic molecule to be synthesized?

Answer 34

* Urea * 1828

Question 35

1858

Answer 35

* American doctors first experimented with the hypodermic needle to directly inject morphine into the bloodstream. * The hypodermic needle was perfected by mid -1800s, and a common instrument in 1870. * Because pain could be controlled with less morphine, it was concluded that injection was less likely to foster addiction.

Question 36

Cocaine

Answer 36

* 1860 * Pure cocaine powder extracted from coca, and was tried on almost every illness known to man. * It was observed that cocaine made workers more productive. * In general, opiates and cocaine were regarded as compounds that were helpful in everyday life. Like coffee, cigarettes, massage, beer today. * Edgar Allen Poe and Ben Franklin used extensively.

Question 37

Germ theory was developed in?

Answer 37

* 1865 * By Pasteur

Question 38

1880

Answer 38

Industrial manufacturing and synthesis became possible.

Question 39

1884

Answer 39

* Purified cocaine became commercially available in the US (25 cents/gram; average wage 20 cents/hr). * Medical experts depicted cocaine as a harmless stimulant that was "no more habit forming than coffee or tea" * Coke- cocaine without alcohol

Question 40

1885

Answer 40

Rabies Vaccine

Question 41

1888

Answer 41

The National Formulary (NF) was created and included some drugs that were not included in the USP.

Question 42

1898

Answer 42

* Bayer aggressively marketed diacetylmorphine to doctors and patients as "safe, non-addictive" substitute for morphine ...coined brand name "heroin". * A "miracle drug" cure-all for whatever ails you. * Free samples of tablets were given to physicians.

Question 43

1899

Answer 43

Acetylsalicylic acid (aspirin) was introduced by Bayer.

Question 44

Opium and cocaine were more readily available in America because?

Answer 44

* The Constitution gave individual states responsibility for health issues, regulation of medical practice, and availability of "pharmacological products". * Many states chose to have no controls at all in the spirit of "free enterprise".

Question 45

1906

Answer 45

* Theodore Roosevelt signed the first Pure Food and Drug Act which designated that drugs labeled USP or NF must conform to the standards set forth. * These two texts were officially combined in 1980. * The Food and Drug Act of 1906 required accurate labeling, but did not prevent sales of drugs. * Claims of therapeutic benefits were still not regulated. * Drugs are not thought to be curative! * American Medical Association approved heroin for use "in place of morphine in various painful infections" - creates huge addiction problem; approximately 5% of the US population is addicted due to prevalence of opium, morphine, heroin and cocaine in various products.

Question 46

Test available for syphilis in?

Answer 46

1906

Question 47

1910

Answer 47

* Arsphenamine was found to cure syphilis. * First drug to be curative.

Question 48

1912

Answer 48

Sherley Amendment prohibited false claims.

Question 49

1914

Answer 49

* Harrison Act required strict accounting of opium and cocoa from entry into US to patient; these products were taxed at each transfer except the patient. * Forbade any trace of cocaine in other remedies (cocaine was available only by prescription); in contrast, heroin could be used in small amounts in non-prescription cough medicine. * This is the first law where the federal government controls prescribing practices.

Question 50

1920

Answer 50

Prohibition ("the noble experiment") banned the sale, manufacture, and transportation of alcohol for consumption until 1933.

Question 51

1922

Answer 51

Insulin was isolated

Question 52

Penicllin

Answer 52

* Discovered in 1928 * Commercially available in 1944 * Won the Noble Prize in 1945

Question 53

1937

Answer 53

Marijuana Tax Act controlled and taxed marijuana

Question 54

The Sulfanilamide Disaster

Answer 54

* 1938 * Sulfanilamide was the new wonder drug, but it was not soluble in most solvents. * One manufacturer started using diethylene glycol in an elixir to improve solubility, and more than 100 people died. * Congress passed the Federal Food, Drug, and Cosmetic Act of 1938 and created the FDA. * The act prohibits the distribution and use of any new drug without the prior filing of a new drug application (NOA). * The FDA became responsible for granting or denying permission to distribute a new product. * The act required that the new product be safe for human use, but it did not require efficacy.

Question 55

1951

Answer 55

DNA double helix described by Watson and Crick

Question 56

1952

Answer 56

* Durham-Humphrey Amendment limited new drugs to prescription-only dispensing. * Prescriptions could not be refilled without the consent of the physician.

Question 57

Polio Vaccine

Answer 57

1954

Question 58

Birth control pill

Answer 58

Approved by the FDA in 1960

Question 59

1962

Answer 59

* A new drug, thalidomide, was being sold OTC in Europe as a sedative and tranquilizer. * It was promising because it appeared to lack toxicity even at high doses. * As a pharmaceutical company waited for US approval from the FDA, birth defects associated with the drug were reported in Europe. * **Congress passed the Kefauver-Harris Drug Amendments which required that drugs were both safe and effective before FDA would approve for marketing.** * Drug sponsors were now required to submit an investigational new drug application (IND) before testing in humans.

Question 60

Measles Vaccine

Answer 60

1963

Question 61

Mumps Vaccine

Answer 61

1967

Question 62

1970

Answer 62

* Insert describing risks and benefits was required by FDA for oral contraception * Comprehensive Drug Abuse Act made marijuana illegal.

Question 63

Tamper-resistant packaging

Answer 63

1982

Question 64

1994

Answer 64

* Congress passed the Dietary Supplement Health and Education Act (OSHEA) which differentiated between regulated, FDA-approved drugs and herbal/dietary supplements. * Supplements were not allowed to have labels claiming that the product can cure or prevent a specific disease. * However, the law does permit claims of benefit relating to nutritional deficiency and general well-being. * Labels and promotions must be submitted to the FDA.

Question 65

Sources of new drugs

Answer 65

* Plants; vinblastine, cortisone, estrogens, taxol * Animal; estrogen from pregnant mares, hormones, factor VIII * Cell cultures; vaccines grown in monkey tissue, chick embryos * Recombinant DNA technology; insulin, EPO, growth hormone, interferon * Antibody technology; diagnostics, many in clinical trials for cancer * Gene therapy; replacement of defective genes, Vitravene, SCIO * Combinatorial chemistry allows rapid screening of compounds

Question 66

lnvestigational New Drug Application

Answer 66

The IND contains * Contact information for sponsor, researchers, etc. * Drug's structural formula, dosage form, etc * Rationale for study and indications to be studied * Previous human experience * hemistry, manufacturing, and quality control information * Pharmacology and toxicology, e.g., mechanism of action, ADME * Clinical protocol * Approval and commitment from an Institutional Review Board (IRB)

Question 67

Clinical Trials

Answer 67

* It takes I 0-15 years on average for an experimental drug to travel from the 1\<1b to U.S. patients. * Only five in 5,000 compounds that enter preclinical testing make it lo human testing. * One of these five tested in people is approved. * 3 phases

Question 68

Phase I of Clinical Trials

Answer 68

* Healthy volunteers * Determine safety and dosage * The initial dose is usually low, typically one-tenth of the highest no-effect dose observed during animal studies. * If this is well tolerated , progressively greater doses are given to new subjects untilsome effects are observed.

Question 69

Phase II of Clinical Trials

Answer 69

* 100-500 sick patient volunteers * Evaluate effectiveness * Look for side effects

Question 70

Phase III of Clinical Trials

Answer 70

* 1,000-5,000 sick patient volunteers * Confirm effectiveness * Monitior adverse reactions from long-term use

Question 71

Blood levels are considered to be a measure of?

Answer 71

Bioavailability

Question 72

The Orphan Drug Act

Answer 72

Passed in 1983 to facilitate the development of drugs for treating diseases that affect less than 200,000 people in the US.

Question 73

New Drug Application

Answer 73

* If safety and efficacy were demonstrated in the clinical trials, a New Drug Application (NDA) is filed. * This application presents all the data from preclinical and clinical trials (Typically at least 100,000 pages). * The FDA is given 6 months to review, but the average review time is over a year. * Funds can be provided by the pharmaceutical companies to expedite review.

Question 74

Postmarketing Surveillance

Answer 74

Phase 4 studies continue to monitor the safety and efficacy of the drug after marketing. These studies may suggest new indication or reveal additional side effects

Question 75

The Drug Price Competition and Patent Term Restoration Act of 1984

Answer 75

* Allows applications for generic copies of approved drugs to be filed thorough an abbreviated new drug application (ANDA) after 17 years. * To gain approval , the generic form must have: * The same active ingredients (inactive ingredients can vary) * Identical strength, dosage form, and route of administration * The same indications and precautions for use and other labeling instructions * Bioequivalency * The same batch-to-batch requirements for identity, strength, purity, and quality * Strict manufacturing conditions that conform to FDA's CGMP

Question 76

Why do we need dosage forms?

Answer 76

1. Amount of drug is too small for people to administer 2. Protect the drug substance from air, moisture, stomach acid 3. Hide bad taste or odor 4. Increase solubility and/or stability 5. Alter release profile to optimize drug action 6. Improve patient compliance

Question 77

Bioavailability

Answer 77

Describes the rate and extent to which an active drug is absorbed from a dosage form and becomes available at the site of action. * Can be portrayed graphically by a concentration vs. time curve

Question 78

Bioequivalence

Answer 78

Bioequivalence refers to the comparison of bioavailabilities of different formulations and/or dosage forms.

Question 79

If we followed the drug in the body over time, we would typically see the drug be?

Answer 79

Absorbed, distributed, metabolized and excreted (ADME).

Question 80

The dosage form can...

Answer 80

* Different dosage forms can dramatically alter the bioavailability even when the same amount of drug is administered. * The dosage form can have a large impact on the effectiveness of the drug even if the AUC (bioavailability) is the same. * The dose (as well as the dosage form) will affect drug performance. This is why different doses are investigated in clinical trials.

Question 81

Milliequivalents

Answer 81

* This unit of measure is related to the **total number of ionic charges** in solution (not the number of particles), when quantifying electrolytes in solution * _Milliequivalents are not used to calculate whether a solution i s isosmotic, and should not be confused with sodium chloride equivalents (E values)! !_

Question 82

The total concentration of cations always?

Answer 82

Equals the total concentration of anions * Any number of milliequivalents of Na+, K+, or any cations always reacts with precisely the same number of milliequivalents of Cl- ,HC0₃-, or any anion.

Question 83

The equivalent weight of a substance is?

Answer 83

Its atomic weight divided by its valence (number of charges). Therefore, the number of equivalents is equal to the moles of charges in solution.

Question 84

Milliequivalents is the number of?

Answer 84

Milliequivalents is the number of millimoles of charges (not millimoles) in solution.

Question 85

Ca²+ has two charges (divalent) and therefore...

Answer 85

Ca²+ has two charges (divalent) and therefore 68 millimoles Ca²+ = 136 mEq Ca²+

Question 86

If the ions are monovalent, the number of mEq is equal to?

Answer 86

If the ions are monovalent, the number of mEq is equal to the number of millimoles. ## Footnote

Question 87

Why is mMol/L (instead of mEq/L) used to describe phosphate concentration?

Answer 87

It's charge varies- the pH changes it

Question 88

Colligative properties depend on the?

Answer 88

* Colligative properties depend on **_the number of particles in solution._** * # of dissolved species in solution

Question 89

Free energy...

Answer 89

* Free energy causes some molecules to leave the solution and enter the vapor phase. * At equilibrium, the rate of molecules leaving the solution is equal to the rate of molecules returning to the solution from the vapor phase. * The molecules in the vapor phase exert a pressure on the solution called the vapor pressure. * Free energy is highest in pure liquids and lower in mixtures. * Therefore, when two liquids are mixed (for example water and ethanol), the free energy of each liquid is reduced due to the presence of the other. * As a result, the vapor pressure of each solvent is reduced in proportion to its mole fraction (X).

Question 90

If n_A equals the number of moles of liquid A, n_B equals the number of moles of liquid B then...

Answer 90

**X_A + X_B = 1.** Therefore, X_A = 1 - X_B and X_B = 1 - X_A

Question 91

Raoult's law states

Answer 91

Raoult's law states that the vapor pressure of component A (pA) is equal to the mole fraction of component A in the mixture times the vapor pressure of pure component A (p°A)

Question 92

p_{A =}

Answer 92

p_A = XA • p°A = (1-X_B) p °A

Question 93

pB=

Answer 93

pB = X_B • p°B = (1-X_A) p °​B

Question 94

Lowering the vapor pressure

Answer 94

* Adding solutes to water lowers the vapor pressure and increases the boiling point * Changes are usually small * Dependent on the number of particles in solution * A colligative property

Question 95

What happens when you add a drug to a solution?

Answer 95

The vapor pressure is lowered Ex: With other molecules in the water it causes enough disorder that the water doesn't want to leave as much ⇒Frat boys want to go out and party but frat boys stay in when a few sorority girls are added to the mix

Question 96

The laws governing colligative properties were?

Answer 96

The laws governing colligative properties were developed for ideal solutions and are therefore only accurate for real solutions that are dilute.

Question 97

The boiling point is the point at which?

Answer 97

The boiling point is the point at which the vapor pressure of the solution equals the external (environmental) pressure. At sea level, p_ext = 1 atm = 760 mm Hg

Question 98

Boiling point elevation | (Non-electrolytes)

Answer 98

ΔT_b=k_bm * Tb is the boiling temperature * k_b is the molal boiling elevation constant (equals 0.51°C/m for water) * m is molality.

Question 99

Freezing point

Answer 99

The freezing point is defined as the point at which the free energy of the liquid equals the free energy of the solid. For example, when water and ice are in equilibrium. * If we add a solute, the free energy, and therefore the vapor pressure, of the solution is reduced.

Question 100

Freezing Point Depression | (Non-electrolytes)

Answer 100

ΔT_f = k_fm kf = the molal freezing point depression constant = 1.86°C/m for water.

Question 101

Osmotic Pressure

Answer 101

Water flows to the region of higher solute concentration due to the reduced free energy of more concentrated solutions. The pressure that must be applied to the more concentrated solution in order to prevent this flow of water is defined as the osmotic pressure.

Question 102

The ideal gas law

Answer 102

The ideal gas law can be used to calculate osmotic pressure. PV = nRT PV = mRT (for dilute solutions) R = 0.082 liter•atm/mole•K **Temperature is in kelvin**

Question 103

Colligative properties- Electrolytes

Answer 103

* Electrolytes dissociate into ions in aqueous solutions, e.g., NaCl dissociates to form Na+ and Cl- * Remember that colligative properties depend on the number of particles in solution. * Therefore, dissociation of electrolytes will affect colligative properties differently than non-electrolytes, and we must consider both the concentration of the electrolyte and its degree of dissociation .

Question 104

Colligative properties- Electrolytes Correction Factor

Answer 104

* Correction factor (i) to correct for dissociation of electrolytes . * For salts that produce two particles (e.g., NaCl), i = 1.8. For salts that produce three particles (e.g., MgCl2), i = 2.6. * For non-electrolytes (e.g., dextrose, ethanol), i= 1. Therefore, the equations for freezing point depression and boiling point elevation become: ΔTf = i kf m and ΔTb = i kb m

Question 105

For _non-electrolytes_, molarity and osmolarity are?

Answer 105

Equivalent * 1 M = 1 Osm/L (particle concentration) because no dissociation occurs. * The number of particles (i.e., millimoles of particles) is often expressed as milliOsmoles. 1 Osm = 1000 mOsm

Question 106

For _electrolytes_, we use P = i mRT to correct for dissociation. Therefore...

Answer 106

Osmolal = i m = Osm/kg P = (Osm/kg) RT Osmolar = i M = Osm/L

Question 107

What is the osmolarity of 0.9% NaCl?

Answer 107

277mOsm•L^-1 (Isotonic Saline) Considered the same osmolarity as blood

Question 108

E value

Answer 108

How much osmotic pressure is contributed by 1 gram of the drug or how much osm pressure exerts thes same pressure as 1 gram of drug =NaCl equivalent (this has nothing to do with charge- all about osmotic pressure)

Question 109

How much NaCl do you know to leave out by using the E value?

Answer 109

(g of drug)(E value) = How much NaCl to leave out because the drug exerts this pressure

Question 110

For intravenous infusion, solutions that are much more concentrated than isosmotic can cause?

Answer 110

* For intravenous infusion, solutions that are much more concentrated than isosmotic can cause phlebitis and tissue damage. * This presents less of a problem in a central vein infusion because the solutions are diluted very rapidly in a large volume of blood.

Question 111

For peripheral vein TPN infusions it is important that solutions not exceed?

Answer 111

900 mOsm/L

Question 112

According to the Bronsted-Lowry theory, An acid is a substance?

Answer 112

An acid is a substance, charged or uncharged, that is capable of donating a proton.

Question 113

According to the Bronsted-Lowry theory, A base is a substance?

Answer 113

A base is a substance, charged or uncharged, that is capable of accepting a proton from the acid.

Question 114

Equilibrium may be defined as a?

Answer 114

Equilibrium may be defined as a balance between two opposing forces or actions. This does not mean that opposing reactions have stopped, but that their rates are equal.

Question 115

The dissociation constant for an **acid**

Answer 115

x = [H₃O⁺] ≈ √(K_ac) \*Not used for buffers K_a = dissociation constant for acids

Question 116

The dissociation constant for a **base**

Answer 116

x = [OH^-] ≈ √(k_bc)

Question 117

The dissociation constant (also known as the ion product) of water is:

Answer 117

Kw = [H₃O⁺] [OH^-] In pure water at 24°C the hydronium and hydroxyl ion concentrations are equal,and they each are at a concentration of 10·7 M. Therefore, at 24°C in pure water: Kw= [10^-7] [10^-7] = 10^-14 * When an acid is added to pure water, some hydroxyl ions, provided by the ionization of water, must always remain. The increase in hydronium ions is offset by a decrease in hydroxyl ions so that **Kw remains constant**. * Therefore, you can calculate the concentration of either of these ions at a given temperature if you know the other. (Note: the temperature dependence of Kw).

Question 118

Charge is critical for virtually everyhting in pharmacy because?

Answer 118

The charge on the drug is going to affect the absorption, solubility, everything!

Question 119

Remember that when salt and acid concentrations are equal (i. e [salt] / [acid] = 1) that. ..

Answer 119

pH= pK_a

Question 120

Buffers

Answer 120

Counteracts the change in pH of a solution

Question 121

What can affect the pH of buffer solutions?

Answer 121

1. Temperature 2. Dilution 3. Presence of drugs 4. Effect of ionic strength from a neutral salt, i.e., NaCl

Question 122

By adding a base (OH) the pH should?

Answer 122

Go up!

Question 124

Atomic Nucleus

Answer 124

Composed of protons and neutrons

Question 126

Number of protons equals

Answer 126

The atomic number in the periodic table

Question 128

Electrons occupy

Answer 128

Discrete states called "orbitals"

Question 130

Atoms like to fill

Answer 130

Their entire outer shell with electrons

Question 132

Orbitals can carry

Answer 132

* s- 2 electrons * p- 6 electrons * d * f

Question 134

Noble Gases

Answer 134

* Some atoms naturally have their outer shells filled * Therefore are not very reactive * They do not need to share any electrons to fill their shell

Question 136

Covalent Bonds

Answer 136

* When atoms SHARE electrons * Very energetically favorable * Relatively strong- the strength of a covalent bond is strongly dependent on the bond length * SHORTER BONDS= STRONGER BONDS

Question 138

Ionic Bonds

Answer 138

* The transfer of electrons between atoms * Cation (+) * Anion (-) * Ions interact due to their opposite charge * Referred to as "salts" * The strength varies depending on the relative electronegativities of the atoms involved * Typically weaker than covalent bonds

Question 140

When identical atoms are involved in covalent bonds, the sharing of electrons is?

Answer 140

Equal (each atom pulls on electrons with the same force due to the same number of protons in their nuclei)

Question 142

When different atoms are involved in a covalent bond the electrons are shared?

Answer 142

Unequal- Unequal sharing of the electrons that creates a polarity

Question 144

Polarity

Answer 144

When one atom has a partial positive charge and one atom has a partial negative charge

Question 146

A difference in charge creates a?

Answer 146

Permanent dipole that can interact with other molecules via dipole-dipole interactions

Question 148

The geometry of the molecule is?

Answer 148

Very important! Some molecules composed of different atoms fo not have a permanent dipole because of their orientation (Ex: CO₂)

Question 150

London Forces or Van der Waals Interactions

Answer 150

* Molecules can induce dipoles in other molecules ("polarizability") and associate via induced dipole-dipole interactions * The strength of these induced dipole interactions is very weak (0.1-1 kcal/mole) * These electrostatic interactions are very dependent on distance * Repulsion- too close together and their electron clouds start running into each other --\> Strong repulsion * Attraction- close enough that the molecules are pulling together * If too far away- nada happens

Question 152

Which atoms are strongly electronegative?

Answer 152

Nitrogen Oxygen Fluorine

Question 154

Nitrogen, Oxygen, and Fluorine can participate in?

Answer 154

A polar interaction involving a hydrogen atom--\> hydrogen bonding

Question 156

Hydrogen Bonds

Answer 156

* Are much stronger than van der Waals interactions * Not as strong as covalent bonds

Question 158

Hydrogen bonds are very prevalent in?

Answer 158

Biological molecules! They play an emnormous role in the structure of DNA and proteins

Question 160

Hydrogen bonds and water molecules

Answer 160

* Dipoles in the water molecule are satisfied by participating in hydrogen bonds with other water molecules * This hydrogen bonded network is energetically favorable (lower free energy) * The disruption of water-water hydrogen bonds is therefore unfavorable

Question 162

Hydrophobic interaction

Answer 162

* When nonpolar molecules that cannot participate in hydrogen bonds are introduced into water, the hydrogen bonding network is disrupted * In order to minimize this disruption, the nonpolar molecules become sequestered together by a hydrophobic interaction → The kids nobody wants to hang out with become sequestered together, even if they don't really want to hang out together, they have to.

Question 164

The association between nonpolar molecules in water is?

Answer 164

Not due to any attraction or "bond" between them, it results from the tendency of the water to maintain its favorable hydrogen bonds with other molecules

Question 166

Due to the hydrophobic interaction?

Answer 166

* Fewer water molecules are in contact with the nonpolar molecules * The water molecules can better maintain their freedom to move and exchange hydrogen bonds * This is an entropy-driven process

Question 168

Molecular interactions turn out to be?

Answer 168

Important for solubility- if we're going to dissolve a molecule in a solvent, it's going to have to interact with that solvent

Question 170

Ideal Solubility

Answer 170

Accounts for how close we are to the melting point and how much energy it actually takes to melt that material

Question 172

What is the most common pharmaceutical solvent?

Answer 172

Water

Question 173

Isotonic Saline

Answer 173

0. 9% NaCl 0. 9g / 100ml of solution