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Chemistry Final Study Guide
Chapters 3 & 4
Mixtures
Homogeneous mixtures:


Composition is uniform throughout



Different parts of the mixture are not visible

Heterogeneous mixtures:


Composition not uniform



Composition varies from one part of the mixture to another



Different parts of the mixture are visible

Elements
o Pure substances that cannot be separated into simpler substances by ordinary laboratory
processes
o Building blocks of elements
Protons (+)
Electrons (-)
Neutrons are neutral
Atomic Number
 Equal to # of protons in an atom
Mass Number
 Equal to # of protons & # of neutrons
# of neutrons = mass # - atomic #

Isotopes
o Atoms of same element that have different mass numbers
o Same # of protons but different # of neutrons
Valence Electrons
-Electrons in the outermost energy level
...


Ions and Ionic Compounds
Octet Rule-tendency for atoms to attain a noble gas electron arrangement
...




By losing electrons a metal atom forms an ion, which has a positive charge
...
Obtains the same electron arrangement as the nearest noble gas
...
The sum of the ionic charges is always
zero
...
The name of a non-metal ion
is obtained by using the first syllable of its elemental name followed by –ide
...

Hydrogen

OH-

Hydroxide

Nitrogen

NH4+

Ammonium

NO3-

Nitrate

NO2-

Nitrite

ClO4-

Chlorate

ClO2-

Chlorite

ClO-

Hypochlorite

CO32-

Carbonate

HCO3-

Hydrogen carbonate

CN-

Cyanide

C2H3O2-

Acetate

SO42-

Sulfate

HSO4-

Hydrogen sulfate

SO32-

Sulfite

HSO3-

Hydrogen sulfite

PO43-

Phosphate

Chlorine

Carbon

Sulfur

Phosphorous

HPO42-

Hydrogen phosphate

H2PO4-

Dihydrogen phosphate

PO33-

Phosphite

Covalent Compounds
Forms when atoms of two non-metals share electrons
...
Move rapidly in a straight line
2
...
Very far apart
4
...
Kinetic energy that increases in raise in temperature
Units for gas measurement and temperature
Pressure (P): atm, mmHg, torr, pascals
...

o When volume decreases the pressure increases and vice versa
...


P1V1 = P2V2

Charles Law (Temperature & Volume)
o Kelvin temperature of gas is directly related to the volume
...

o Temperature of gas increases, volume increases
...

o Pressure that gas would exert if it were by itself in the container
...

o Total pressure exerted by gases in a mixture is sum of p
...
of those gases
...




Consists of solvent (greater amount) & one or more solutes (lesser amount)
...




Not separated by filtration but by evaporation
...


Solvent
Water is the most common solvent
...

Electrolytes
Strong Electrolytes
 Disassociate in H2O, producing positive and negative ions
...

 In equations show formation of ions in (aq) solutions
...

 In water forms a solution of a few ions and mostly undisassociated molecules
...

 Do not produce ions in water
...

Solubility


Maximum amount of solute that dissolves in a specific amount of solvents
...


Unsaturated Solutions


Contain less than max amount of solute
...


Saturated Solutions


Contain max amount of solute that can dissolve
...


Colloids
 Have medium-sized particles
...

 Can be separated by semi-permeable membrane
...
X
...

Suspensions
 Very large particles
 Settle out
 Can be filtered
 Must be stirred to stay suspended
 E
...
blood platelets, muddy water, and calamine lotion
...

o Level of the solution with higher solute concentration rises
o Concentrations of 2 solutions become equal with time
Osmotic pressure
o Produced by solute particles dissolved in a solution
o Equal to pressure that would prevent the flow of additional water into the more
concentrated solution
o Greater as number of dissolved particles in the solution increases
Isotonic Solutions


Exerts same osmotic pressure as Rbc’s



Known as physiological solution



Of 5 % glucose or
...


Hypotonic Solutions


Lower osmotic pressure than Rbc



Lower concentration than physiological solutions



Causes water to flow into Rbc



Causes hemolysis: Rbc will swell and burst
...

Acids with H and a polyatomic ion are named by changing the end of name of polyatomic from
-ate to ic acid or -ite to ous acid
...
ClO3- Chlorate  Chloric acid)

Arrhenius bases


Produce OH- ions in water



Taste bitter or chalky



Are electrolytes



Feel soapy and slippery



Neutralizes acids

Bases with OH- are named as the hydroxide of the metal in the formula
...
A base, H2O, accepts H+ to form
conjugate acid, H3O+
...
One water molecule acts as an acid, while
another acts as a base
...

Kw = [H3O+] [OH-]
[1
...
0 x 10-7 M]
= 1
...

Buffers
In body, reabsorb H3O+ or OH- from foods and cellular processes to maintain pH
...

Molecular formula
Examples: C2H6, CH4, C3H8
Condensed structural formula
CH3-CH2-CH2-CH3
Expanded formula

Combustion

 Alkanes react with oxygen
 CO2, H2O and energy are produced
 Alkane + O2  CO2 + H2O + heat
Chapter 11 & 12
Naming alkenes
-ene ending
*known common names
Ethene  ethylene
Propene  propylene

Naming alkynes
-yne ending

Cis-Trans Isomers


In an alkene, double bond



Rigid



Holds attached group in fixed positions



Makes cis-trans isomers possible

Cycloalkenes

Polymers of alkene
o Large, long-chain molecules
o Composed of small repeating units called monomers
o Made from reaction of small alkenes

Aromatic compounds
Benzene

Naming aromatic compounds:
-With benzene as parent chain
-With one side group named in front
of benzene

Toluene Aniline Phenol
Alcohols
Naming: replace –e with –ol
...

CH3-COOH  methanoic acid
Aldehydes
Naming: drop –e in the alkane name and change to –al
...


IUPAC: methanal or Common: formaldehyde
Ketones
Naming: drop the –e in the alkane and replace with –one
...


IUPAC: butanone, Common: ethyl methyl ketone
Reactions
Hydrogenation: CH3-CH=CH-CH3 + H2 (Pt, Ni, or Pd) CH3-CH2-CH2-CH3
CH3-C≡C-CH3 + 2 H  (Pt, Ni, Pd) CH3-CH2-CH2-CH3
Hydration
 Water adds to double bond
 H atom bond to one C in the double bond
 OH atom bonds to the other C
CH3-CH2-CH2-CH=CH2 + H2O  (H+) CH3-CH2-CH2-CH-CH3
‫׀‬
OH

When there is an unequal # of H atoms
 H atom bonds to C in double bond with more H atoms
 OH bonds to C in double bond with fewer H atoms
CH3-CH=CH2 + H2O  (H+) CH3-CH-CH2
‫׀‬
‫׀‬
OH H
Dehydration of alcohols to form alkenes
CH3-CH2  (H+/ heat) CH2=CH2 + H2O
‫׀‬
OH
Oxidation/ Reduction of alcohols

O

O

‖

‖

CH3-CH3   CH3-CH2-OH CH3-C-H CH3-C-OH
Oxidation of thiols
[O]
CH2-SH-HS-CH2→ CH2-S-S-CH2 + H2O
Chapter 14
Esters
Naming: first word indicates the alkyl part of the alcohol
...
IUPAC: use names for the acid
...

O
‖
CH3-C-O-CH3 IUPAC: methyl ethanoate

Common: methyl acetate

Alkaloids
 Physiologically active nitrogen-containing compounds
 Obtained from plants
 Used as anesthetics, antidepressants, and stimulants such as caffeine
 Often addictive
Types: cocaine, caffeine, nicotine, morphine and codeine
...

O
‖
CH3-C-NH2 IUPAC: Ethanamide Common: acetamide
Naming: in both the common and IUPAC names, simple amides are named by dropping the oic
acid or ic acid from the carboxylic acids name and adding the suffix amide
...


Benzamide
Amines
Are derivatives of ammonia that contain N attached to one or more alkyl or aromatic groups
...
When two or more alkyl groups
bonded to the nitrogen atom, they are listed in alphabetical order using prefixes di and tri
...

An amino acid is polar when he R group is an alcohol, thiol, or amide
...

An amino acid is basic when the R group is an amine
...


Amino acids as Bases
In solution more acidic than the pI,


The COO- in the amino acid accepts a proton
...




Forms between the carboxyl group of one amino acid and the amino group of the next
amino acid
...




Names the last amino acid with the free carboxyl group (COO-) by its amino acid name
...

o the backbone of a peptide chain or protein
...

o Has a primary structure of two polypeptide chains linked by disulfide bonds
...

Secondary Structure- Alpha Helix
o A three-dimensional spatial arrangement of amino acids in a polypeptide chain
...

o A corkscrew shape that looks like a telephone cord
...

o Has hydrogen bonds between chains
...

o Is typical of fibrous proteins, such as silk
...

o Typical of collagen, connective tissue, skin, tendons, and cartilage
...

o Is determined by attractions and repulsions between the side chains of the amino acids in
a peptide chain
...

o Carry out synthesis, transport, and metabolism in the cells
...

Quaternary Structure
o Is the combination of two or more protein units
...

o Is stabilized by the same interactions found in tertiary structures
...

o Such as alpha keratins make up hair, wool, skin, and nails
...

Denaturing Proteins



The disruption of bonds in the secondary, tertiary and quaternary protein structures
...




Heavy metal ions that react with S-S bonds to form solids
...


Enzymes
Proteins that


catalyze nearly all the chemical reactions taking place in the cells of the body
...


Names of Enzymes


Usually ends in –ase
...
For example, sucrose catalyzes the reaction of sucrose
...
For example, oxidases catalyze oxidation
...


Enzyme-Catalyzed Reaction


Substrate attaches to the active site



An enzyme-substrate (ES) complex forms



Reaction occurs and products are released



An enzyme is used over and over again

Lock-and-Key Model


Active site has a rigid shape



Enzyme only binds substrate that exactly fits the active site

Induced-Fit Model


Enzyme structure is flexible, not rigid



Enzyme and substrate adjust the shape of the active site to bind substrate



Shape changes improve catalysis during reaction

Diagnostic Enzymes


Determine the amount of damage in tissue



That are elevated may indicate damage or disease in a particular organ

Isoenzymes


Catalyze the same reaction in different tissues in the body



Can be used to identify the organ or tissue involved in damage or disease



Examples: LDH consists of five isoenzymes (prevalent in heart muscle and skeletal
muscle)

Temperature and Enzyme Action


Most active at optimum temperature (usually 37˚ C in humans)



Show little activity in low temperature



Lose activity in high temperatures as denaturation occurs

pH and Enzyme Action


Most active at optimum pH



Contain R groups of amino acids with proper charges at optimum pH



Lose activity in low or high pH as tertiary structure is disrupted

Enzyme Inhibition
Inhibitors are molecules that cause a loss of catalytic activity and prevents substrates from fitting
into the active site
...

 Translation
tRNA molecules bring amino acids to mRNA to build a protein
...


tRNA
o has a triplet called an anticodon that complements a codon on mRNA
o bonds to a specific amino acid at the acceptor stem
Termination
o all the amino acids are linked
o the ribosome reaches a “stop” codon: UGA, UAA, or UAG
o there is no tRNA with an anticodon for the “stop” codons
o the polypeptide detaches from the ribosome (acts as a functional protein)

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