Chemistry 1110

the development of a chemical reaction

"for any reversible reaction in a closed system, whenever the opposing reactions are occurring at different rates, the faster reaction will gradually become slower, and the slower reaction will gradually become faster. finally, the reaction rates become equal, and equilibrium is established."

messenger RNA

"photocopy" of the protein plan

carboxyl group

-COOH

naming alkanes prefixes

1 carbon atom - meth 2 - eth 3 - prop 4 - but 5 - pent 6 - hex 7 - hept 8 - oct 9 - non 10 - dec

two things are needed when considering equilibrium calculations:

1. equilibrium equation 2. equilibrium constant expression (moles/liter)

how to predict the favored direction of an acid-base reaction

1. for a given pair of reactions, write the equation for the transfer of one proton from one species to another 2. label the acid and base on each side of the equation 3. determine which side of the equation has both the weaker acid and the weaker base, and that side identifies the products in the favored direction

naming alkanes

1. identify as the parent alkane the longest continuous chain, and name according to the prefix associated with the number of carbons 2. identify the number the carbon atom to which the alkyl group (or other species) is bonded to the chain 3. identify the branched group (or other species) 4. if the same alkyl group, or other species, appears more than once, indicate the number of appearances by di-, tri-, etc., and show the location of each branch by number 5. if two or more different alkyl groups, or other species, are attached to the parent chain, they are name din alphabetical order

oxidation # assignment rules

1. the oxidation number of each atom in any elemental substance is 0 2. the oxidation number of a monatomic ion is the same as the charge of the ion 3. the oxidation number of combined oxygen is -2, except in OF₂ it is +2 4. the oxidation number of a combined hydrogen is +1, except in a hydride ion it is -1 5. in any molecular or ionic species, the sum of the oxidation numbers of all atoms in a molecule or polyatomic ion is equal to the charge on the species

general bronsted-lowry theory equation

B + HA⁺ → HB⁺ + A⁻

the general formula of a cycloalkane is

C(n)H(2n)

naming alcohols

CH₄O alkyl group + alcohol: methyl alchol alkane prefix + -ol: methanol

central dogma of molecular biology

DNA replicates itself → transcription → RNA → translation →proteins

an acidic solution has a higher ____ concentration than _____ concentration.

H⁺ , OH₋

the equilibrium constant (K)

K = [C]^c ∙[D]^d / [A]^a ∙ [B]^b •when writing an equilibrium constant expression, use only the concentrations of gases (g) or dissolved substances (aq). do not include solids or liquids

the acid constant, Ka =

Ka = [H⁺][A⁻]/[HA] HA (aq) ↔ H⁺ (aq) + A⁻ (aq)

equilibrium constant for water

Kw = [H⁺][OH⁻] = 1.0 x 10⁻¹⁴ at 25° C there is an inverse relationship between [H⁺] and [OH⁻]: if one concentration goes up, the other goes down

reduction

a gain of elections or a reduction in oxidation number

oxidation

a loss of electrons or an increase in oxidation number

half reaction

a reaction that cannot occur by itself. oxidation-reduction reactions can be divided into an oxidation half-reaction equation and a reduction half-reaction equation. addition of these gives a balanced equation for a redox reaction

amphoteric

a substance that can behave as an acid in one case and a base in another

bronsted-lowry acids vs. bases

acids are compounds from which protons (H⁺) can be removed (proton donor), while bases are compounds that removes protons (proton acceptor)

naming esters

alcohol alkyl group + acid anion: methyl acetate alcohol alkyl group + acid alkane prefix + oate: methyl ethanoate C₃H₆O₂

alkyl group

an alkane from which one hydrogen has been removed, (-CH₃), where the dash indicates a bond that the alkyl is able to make with another atom

salt bridge

an apparatus that connects the two half cells in a voltaic cell so that the cell maintains electrical neutrality without bulk mixing of solutions

enzymes/substrate/active site/inhibitors

an enzymes substrate binds at the enzymes active site, and enzyme inhibitors compete with the substrate for the active site

hydroxyl group

an organic functional group, -OH, characteristic of alcohols

transition state

an unstable intermediate species formed during a collision of two reacting particles. the properties of a transition state cannot be described because the complex decomposes almost as soon as it forms.

naming ethers

both alkyl groups + ether: ethyl methyl ether alkyl group + -oxy- + alkane: methoxyethane C₃H₈O

carbohydrates

can be monosaccharides (simple sugars that cannot be converted to smaller carbohydrates), disaccharides (formed from two simple sugars), or polysaccharides (formed from many sugars) aldehydes or keytones with two or more -OH groups

chain-growth vs. step growth polymers

chain-growth: formed by repeated addition reaction of an alkene monomer to give an alkane-like polymer chain step-growth: formed by repeated condensation reactions to give a polymer chain with repeated ester or amide functional groups

conjugate acid-base pairs

combinations such as base B and acid HB⁺ as well as acid HA and base A⁻ that result from an acid losing a proton or a base B + HA⁺ → HB⁺ + A⁻ base B and acid HB⁺ are conjugate pairs acid ha and base A⁻ are conjugate pairs

naming amides

common acid prefix + -amide: formamide alkane prefix + -amide: methanamide CH₃NO

naming carboxylic acids

common name + acid: formic acid alkane prefix + -oic + acid: methanoic acid HCO₂H

naming aldehydes

common prefix + aldehyde: formaldehyde alkane prefix + -al: methanal CH₂O

isomers

compounds with the same molecular formula but different molecular structures

electrodes

conductors by whic electric charges enter or leave electrolytes

DNA

deoxyribonucleic acid (DNA): stores genetic information and transmits that information to the next generation during cell division

amides

derivatives of a carboxylic acid in which the hydroxyl part of the carboxyl group is replaced by an -NH₂ group R-CONH₂

example of monosaccharide

fructose

example of polysaccharide

glycogen

dipeptide

molecule composed of two amino acids

naming amines

name alkyl groups + amine: methylamine amino- + alkane: aminomethane CH₅N

naming ketones

name both alkyl groups + ketone: methyl ethyl ketone (number carbonyl carbon) + alkane prefix + -one: butanone; 2-pentanone C₄H₈O

nucleotides

nucleic acid monomers that are composed of a) an N-containing cyclic molecule called a base (image), b) a sugar, either ribose or deoxyribose, and c) one or more phosphate groups attached to the -OH groups of the sugar

amines

organic derivatives of ammonia, NH₃, that is formed by replacing one, two, or three hydrogens in an ammonia molecule with an alkyl group RNH₂ R₂NH R₃N

pH and pOH

pH = -log[H⁺] pOH = -log[OH⁻] [H⁺] = 10^(-pH) [OH⁻] = 10^(-pOH) pH + pOH = 14

macromolecules

polymeric molecules with molar masses starting from about 5000 g/mol and going up from there

transcription

process by which DNA creates a specific protein molecule

replication

process by which DNA duplicates itself during cell division

translation

process by which genetic information mRNA is decoded to produce a protein molecule

if K is very large (>1), there are mostly _________, and the the reaction will be favored towards the __________ direction. if K is very small (<1), there are mostly __________, and the reaction will be favored in the _______ direction . if K is close to 1, the reaction will be _______ .

products, forward reactants, reverse equal

gene

protein blueprint contained in DNA

substitution reaction

reaction in which a hydrogen atom in an alkane is replaced by an atom of another element

halogenation reaction

reaction with a halogen that both alkenes and alkanes undergo

RNA, tRNA, mRNA

ribonucleic acid (RNA): assists in the transmission of genetic information by transferring the correct amino acid during protein synthesis mRNA: carries instructions for protein synthesis from DNA to ribosomes tRNA: delivers specific individual amino acids to the ribosomes

saturated vs. unsaturated

saturated: each carbon is bonded to the maximum four other atoms and there is no room for the carbon atom to form another bond unsaturated: carbon is bonded to fewer than the maximum number of atom sit is capable of

α-helix structure

secondary structure that allows for the maximum hydrogen bonding and the greatest stability in a continuous series of loops stabilized by INTRAchain hydrogen bonds

β-pleated sheet

secondary structure that allows for the maximum hydrogen bonding and the greatest stability in a curtain with sharp angles, like pleats stabilized by INTERchain hydrogen bonds

strong vs. weak acid

strong acids are ones that ionize almost completely and lose their protons readily, while weak acids ionize but only slightly

strong vs. weak base

strong bases have a strong attraction for protons, while weak bases dissociate only slightly in aqueous solutions and have a weak attraction for protons

ribosome

structure outside of the nucleus where protein synthesis occurs

example of disaccharide

sucrose

methyl group

the one carbon alkyl structural group -CH₃

induced fit model

the shape of the substrate is a close, but not exact, match to the shape of the active site of the enzyme. as the substrate binds to the enzyme, either or both molecules change shape slightly.

naming alkenes and alkynes

they follow the same naming system as alkanes, but with respective suffices -ene and -yne

Arrhenius theory of acids and bases

•Arrhenius acid: substance that increases the concentration of H+ ions when dissolved in water •Arrhenius base: substance that increases the concentration of OH ions when dissolved in water •acids react with CO₃²⁻ to produce CO₂ •acids react with some metals to produce H₂ •bases react with some metal ions to produce solids

aldehydes

•R-CHO •easily oxidized •can be reduced to alcohols

ketone

•R-CO-R' •resist oxidation •can be reduced to alcohl

aromatic hydrocarbon

•a hydrocarbon with one or more benzene rings •an alkyl group, halogen, or other species may replace hydrogen on a benzene ring

benzene ring

•a planar, 6-carbon structural unit connected by delocalized reactions •benzene is nonpolar and liquid at room temperature

alkanes

•alkane: each carbon atom forms single bonds to four other atoms, and there are no multiple bonds •C(n)H(2n+2) •all alkanes are nonpolar •cycloalkanes: have all carbon-carbon single bonds with at least some of the carbon atoms forming a ring •alkanes with fewer than 5 carbons have weak intermolecular forces, low boiling points, are gases at room temperature, and are all used as fuels •alkanes with grater than 5 carbons are liquid at room temperature and make up diesel fuel and lubricating oils

bronsted-lowry theory of acids and bases

•an acid-base reaction is a proton transfer reaction in which the proton is transferred from the acid to the base •acids are compounds from which protons can be removed, and a bases are compounds that can remove protons from an acid •anything that can take away a proton is a base

hydrocarbon

•binary compounds of carbon and hydrogen

classical properties of bases

•bitter taste •neutralize acids •form precipitates when added to solutions of most metal ions •liquid solutions of bases feel slipper or soapy

alcohols

•consist of an alkyl group and hydroxyl group, R-OH •the suffix -ol denotes an alcohol

esters

•esterification: reaction between an acid and an alcohol, the products of which are an ester and water •R-CO-OR'

ethers

•ether: removal of both hydrogen molecules from a water molecule and is completed when to alkyl groups bond to the oxygen •R-O-R' •prepared by dehydrating alcohol •relatively unreactive, highly flammable, and have low boiling points

alkenes

•hydrocarbons with at least one double bond •unsaturated

alkynes

•hydrocarbons with at least one triple bond •unsaturated

le chatelier's princples

•if an equilibrium system is subject to change, processes occur that tend to partially counteract the initial change, thereby brining the system to a new position of equilibrium •three effects: the concentration effect, the volume effect, and the temperature effect

le chatelier's principle: the temperature effect

•if heat is removed, the equilibrium will shift in the direction that produces heat •if heat is added, the equilibrium must shift in the other direction to "use up" the heat

le chatelier's principle: the volume effect

•if the volume is reduced, pressure increases, and therefore the equilibrium will shift to side with fewer molecules •if the volume is increased, pressure decreases, so the reaction will shift towards the side with more molecules to increase the pressure •only gaseous molecules are involved in pressure adjustments, so don't count s, l, or aq

the collision theory of chemical reactions

•if two molecules are to react chemically, they must come into contact with each other • what we see as a chemical reaction is the overall effect of a huge number of individual collisions between reacting particles •basically, for an individual collision to result in a reaction, the particles must have enough kinetic energy and the proper orientation to create a violent, bond-breaking collision •the rate of reaction depends on the frequency of effective collisions

amino acid

•molecule that contains both an amine (RNH2) group and a carboxylic acid (R-COOH) group •bond between amino acid is called a peptide linkage

4 structures of proteins

•primary structure: its sequence of amino acids •secondary: local spatial layout of the amino acid backbones •tertiary: describes the spatial arrangement of the entire polypeptide chain (3D) •quaternary: describes how its polypeptide chains are arranged to form a protein molecule (AKA how multiple polypeptide chains are arranged in relation to one another)

classical properties of acids

•sour, biting taste •react with carbonate ions and release carbon dioxide •react with and neutralize a base •release hydrogen when they react with particular metals

conditions that affect the rate of a chemical reaction

•temperature - reactions are faster at higher temperatures •the presence of a catalyst •concentration - the more particles there are i a given volume, the more frequently collisions will occur and the more rapidly the reaction will take place

the character of an equilibrium

•the equilibrium is closed in the sense that no substance can enter or leave the immediate vicinity of the system; all substances on one side of an equilibrium reaction must remain to form the substances on the other side •the equilibrium is dynamic; the reversible changes occur continuously at the particulate level in a state of dynamic equilibrium, even though there is no macroscopic appearance of change the things that are equal in an equilibrium are the forward rate of change and the reverse rate of change. •the amount of substances present in an equilibrium are not necessarily equal

reducing agent

•the species from which the electrons are removed •species that is itself oxidized

oxidizing agent

•the species that removes electrons •the species that is itself reduced

carboxylic acids

•weak acids that release a proton from the carboxyl group on ionization •R-COOH