IB Allure Definitions
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IB Allure Definitions mostly by Jobin
Compound: Two or added types of atoms chemically affirmed together.
Bond, covalent: Bonding by the administration of e-. The e- are aggregate and admiring by both nuclei consistent in a directional band amid the two atoms.
Forces, dipole:dipole: Permanent electrostatic armament of allure amid arctic molecules. Stronger than van der Waals’.
*Ideal gas: A gas for which the accord pV = nRT holds true.
*Liquid: Has anchored aggregate and takes up appearance of container.
*Maxwell-Boltzmann distribution: Graph assuming the administration of active energies apartof molecules.
*Molar volume: At 273 K and 1 atm, one birthmark of any gas will absorb 22.4 dm3.
*Solid: Has anchored appearance and anchored volume. Particles captivated calm by intermolecular armament in a anchored position.
*Bond enthalpy: The boilerplate enthalpy change of breaking a band amid aerial atoms into its basic aerial atoms.
*Born-Haber cycle: Energy cycles for the accumulation of ionic compounds. If there is little acceding amid the abstract and beginning values, this could announce a amount of covalent character. ?Hf = ?Hat(1) + ?Hat(2) + ?HIE(1) + ?HEA(2) – ?HLatt
*Calorimetry: A accessory for barometer enthalpy changes for reactions. In a simple calorimeter all the calefaction acquired in an exothermic acknowledgment is acclimated to accession the temperature of a accepted accumulation of water.
*Electron affinity: Enthalpy change if an e- is added to an abandoned atom in the aerial state.
*Endothermic: A acknowledgment in which activity is absorbed. ?H is +. Reactants added abiding than products.
*Enthalpy: The centralized activity stored in the reactants. Alone changes in enthalpy can be measured.
*Entropy: A admeasurement of the ataxia of a system. The complete anarchy can be begin in agreement of the anticipation of a accompaniment existing. Things causing anarchy to increase: 1) access of amount of moles of aerial molecules; 2) change of accompaniment from solid to aqueous or aqueous to gas
*Exothermic: A acknowledgment in which activity is evolved. ?H is –. Articles added abiding than reactants.
*Gibb’s chargeless energy: Must be – for acknowledgment to be spontaneous. ?G = ?H – T?S
*Heat: A admeasurement of the absolute activity in a accustomed bulk of substance.
*Hess’ law: Enthalpy change for a acknowledgment depends alone on aberration amid enthalpy of articles and enthalpy of reactants ? absolute of pathway.
*Lattice enthalpy: The endothermic action of converting a apparent solid into its aerial ions, or the about-face exothermic process. The filigree enthalpy increases with abbreviating admeasurement of the ions and accretion charge.
*Spontaneous: A acknowledgment that has a accustomed addiction to occur.
*Standard conditions: 298 K and 1 atm.
*Temperature: A admeasurement of the boilerplate active energy.
It should be acclaimed that some of the activity definitions can be advised in the about-face administration with a agnate change of assurance for the energy. Band accumulation = exothermic ?H negative, band break = endothermic ?H positive
*Standard enthalpy of vaporisation: The activity appropriate to vaporise one birthmark of a liquid.
*Enthalpy of atomisation: The activity appropriate to aftermath one birthmark of aerial atoms from an aspect in its accepted state.
*Bond break enthalpy: The activity change if one birthmark of a specific band is torn or created beneath accepted conditions.
*Standard band enthalpy: The boilerplate activity change if one birthmark of a specific blazon of band is torn or created beneath accepted conditions.
*Enthalpy of Combustion: The activity appear if one birthmark of a admixture is austere in balance oxygen.
*Standard enthalpy of formation: The activity change if one birthmark of a admixture is formed from its basic elements in their accepted states beneath accepted conditions.
*Standard enthalpy of solution: The activity change if one birthmark of a actuality is attenuated in an absolute bulk of baptize beneath accepted conditions.
*Standard aridity enthalpy: The activity change if a atom is taken from absolute break in the aerial accompaniment to its position in an aqueous lattice.
*Ionisation energy: The activity appropriate to aftermath one birthmark of aerial ions from one birthmark of aerial atoms by abatement of one birthmark of electrons.
*Lattice enthalpy: The activity change if one birthmark of an ionic actuality is torn into its basic atoms at absolute separation.
*Activated complex: Created during a bimolecular process. Not a actinic actuality which can be isolated, but consists of reacting particles in which bonds are in the action of getting torn and formed. Can breach down to anatomy either the articles or aback to the aboriginal reactants.
*Activation energy: The minimum bulk of activity appropriate for a acknowledgment to action amid two particles. The additional claim is that the particles accept to accept an adapted geometry of collision.
*Arrhenius equation: An blueprint assuming the accord amid the temperature and the amount constant. K=Ae(-Ea/RT)
*Bimolecular process: A acknowledgment which occurs if two breed bang and interact.
*Catalyst: Provide an another alleyway for a acknowledgment such that the activation activity appropriate to ability the activation circuitous is lowered. Can be disconnected into two types: akin catalysts are in the aforementioned appearance as the reactants, while amalgamate ones are in a altered phase. Amalgamate catalysts tend to plan by accompany the agitator particles into abutting alignment by adsorbing them assimilate the catalytic surface.
*Concentration, aftereffect of: Increasing absorption after-effects in an added abundance of collisions. Area the ambit evens out depends on the absolute bulk of the attached reagent involved. If the absorption of the attached reagent is angled after advantage in aggregate for the access in amount, then ambit will balance at a altered level.
*Half-life: The time taken for the absorption of the agitator to abatement to bisected of its antecedent value.
*Molecularity: Number of breed demography allotment in any defined move in the reaction.
*Order of reaction: The amount is consistently proportional to the absorption of a agitator aloft to a power, area the ability is the adjustment of the acknowledgment with account to that reactant.
*Rate constant: The connected of arrangement in the amount expression. Assemblage is: (mol dm-3)1 – all-embracing adjustment s-1.
*Rate expression: An blueprint that shows the accord amid the concentrations of the reactants and the amount of the reaction. Every breed in the amount announcement haveto action in the amount free move or in an calm occurring afore it.
*Rate of reaction: The amount of access of concentration/mass of one of the articles or the amount of abatement of concentration/mass of one of the reactants.
*Rate-determining step: The slowest move of a reaction. This determines the amount of the absolute reaction.
*Surface area, aftereffect of: Increasing apparent breadth after-effects in an added abundance of collisions.
*Temperature, aftereffect of: Increasing the temperature increases the abundance of collisions of the molecules, but added importantly, increases the admeasurement of molecules with active activity greater than or according to the activation energy.
*Unimolecular process: A action in which a individual breed break down into two or added products.
*Closed system: A arrangement in which neither amount nor activity can be absent or gained. An calm can never action in a arrangement that is not closed.
*Contact process: The amalgam of sulphuric acid, area V2O5 is acclimated as a catalyst.
*Equilibrium constant: For a acknowledgment aA + bB ? cC + dD, area the baby belletrist are coefficients and basic belletrist are the reactants, the calm connected is [C]c[D]d/[A]a[B]b. Capricious units.
*Equilibrium, dynamic: An calm in which the ante of the advanced and about-face reactions are the same.
*Haber process: The amalgam of ammonia, area Fe is acclimated as a catalyst.
*Optimum temperature: For exothermic reactions such as the Haber process, the optimum temperature is the best accommodation amid crop and rate.
*Homogeneous reaction: A acknowledgment in which all the breed complex are in the aforementioned phase.
Le Chatelier’s principle: If an calm is subjected to a stress, the calm will about-face to abbreviate the aftereffect of the stress.
*Phase equilibrium: When the amount of dehydration is according to the amount of condensation.
*Vapor pressure: The fractional burden of a vapor. Baking occurs if a liquid’s breath burden equals the alien pressure. The stronger the intermolecular armament the lower the breath burden at a accurate temperature.
*Acid properties: React with:
**Indicators;
**Bases, in abatement reactions (form a alkali and baptize with hydroxides and metal oxides; anatomy a alkali with ammonia);
**Reactive metals (those aloft chestnut in acuteness series) (form alkali and hydrogen);
**carbonates and hydrogencarbonates (form a salt, CO2 and water).
*Amphoteric: Can accept the backdrop of both a abject and an acid, depending on whether it is reacting with a abject or an acid.
*Bronsted-Lowry: An acerbic is authentic as a proton donator, while a abject is a proton acceptor.
*Buffer: A band-aid that resists changes in pH if baby amounts of acerbic or acrid are added to it. If a baby bulk of acerbic is added, the balance of H+ ions causes the calm to about-face to the larboard ? balances the difference. If a baby bulk of acrid is added, the OH- ions acknowledge with the H+ ions to anatomy water. The abatement in [H+] is compensated for by an calm about-face to the right. Carnality versa for acrid buffers. Absorber solutions are create by several means:
**strong abject + balance anemic acid;
**strong acerbic + balance anemic base;
**weak acerbic + aforementioned acid’s salt;
**weak abject + aforementioned base’s salt.
*Charge density: Charge over size.
*Concentrated: High amount of moles of solute per dm3 of solution.
*Conductivity: The added a band-aid is dissociated into its ions, the greater its conductivity.
*Conjugate: The breed actual afterwards an acerbic has absent a proton (conjugate base) or a abject has acquired one (conjugate acid). pKa + pKb = pKw
*Diprotic: Where one birthmark of sulphuric acerbic produces two moles of hydrogen ions, e.g. H2SO4.
*End point: The point at which the indicator changes blush alotof rapidly.
*Equimolar: Containing according concentrations.
*Equivalence point: Where the acerbic and abject are in equimolar quantities. Absolutely abundant to acknowledge with anniversary other.
*Indicator: A anemic acerbic or abject in which the dissociated anatomy is a altered blush to the undissociated form. The end point occurs if the pH is about according to the pKin value, bold that the blush changes if [In-] ? [HIn]. Ideally, the end point corresponds to the adequation point in a titration.
*Lewis theory: An acerbic is authentic as an e- acceptor (e.g. BF3) and a abject is an e- donator (e.g. NH3) by dative bond.
*Monoprotic: Where one birthmark of the acerbic produces one birthmark of hydrogen ions, e.g. HCl.
*pH: Power of hydrogen. – log [H+]
*Salt hydrolysis: The action by which a alkali is torn down by water. The acidity of the alkali depends on:
1) its derivations (salts acquired from a able acerbic and anemic abject will be acerb in solution, because that the ions of the anemic abject will combine, abrogation an balance of H+. The able acerbic will not amalgamate as it is absolutely dissociated, as per definition. Carnality versa with able acerbic and anemic base);
2) allegation body of cation (high allegation body after-effects in able allure to the abandoned brace of one of six baptize molecules surrounding the ion, a action by which the baptize atom loses a hydrogen ion, i.e. abrogation the band-aid acidic).
*Strong: An acerbic or a abject that dissociates absolutely into its ions. Ka >> 1. Some able acids: hydrochloric, sulphuric, nitric (weaker than additional two). Able bases: hydroxides of acrid metals.
*Titration: Technique for quantitative admeasurement of absorption of a solution. Accede if 90% of the appropriate abject has been added to a 1M able acerbic that is to be neutralized. Alone 10% of the acerbic remains, acceptation 0.01M, giving a pH of 2. If 99% has been added, the pH is 3, etc.
*Water, ionic artefact of: The calm connected for the break of baptize into its ions, area [H2O] is taken to be constant. Amount of Kw increases as temperature is increased, as the break is an endothermic process. pKw
*Weak: An acerbic or abject that alone hardly dissociates into its ions. Ka << 1. Some anemic acids: ethanoic, carbonic. *Weak bases: ammonia, aminoethane.
*Anode: Where blaze takes place. In electrolysis, it is the + electrode and anions are admiring here.
Cathode: Where abridgement takes place. In electrolysis, it is the – electrode and cations are admiring here.
*Electrolysis: Passage of electric accepted through an electrolyte. Bulk of acquittal is afflicted by: 1) current; 2) allegation on ion, 3) continuance of electrolysis.
*Electrolyte: A actuality which does not conduct electricity if solid, but does if aqueous or in aqueous band-aid and is chemically addle in the process.
*Electrolytic cell: Used to create non-spontaneous redox reactions action by accouterment activity in the anatomy of electricity from an abiding source.
*Electroplating: A action of blanket one metal with a attenuate band of addition metal, by electrolysis.
*Half cell: A metal in acquaintance with an aqueous band-aid of its own ions.
*Oxidation number: Ox. no. of:
a) elements: 0;
b) ion: its charge;
c) oxygen: -2 (except in peroxides, -1);
d) hydrogen: +1 (except metal hydrides, -1);
e) fluorine: -1.
*Oxidation: The accident of e-, the accretion of oxygen, the accident of hydrogen or the access in blaze number.
*Oxidizing agent: A actuality that readily oxidizes additional substances. Acerbic agents are appropriately reduced. The college the blaze number, the bigger an acerbic abettor it is, generally.
*Reactivity: A admeasurement of the address of a actuality to accretion or lose e.. The stronger the abbreviation abettor or acerbic agent, the added acknowledging it is.
*Redox reaction: A acknowledgment in which there is a alteration of e-, i.e. abridgement and blaze occurring simultaneously.
*Reducing agent: A actuality that readily reduces additional substances. Abbreviation agents are appropriately oxidized.
*Reduction: The accretion of e-, the accident of oxygen, the accretion of hydrogen or the abatement in blaze number.
*Salt bridge: Allows the chargeless movement of ions in a voltaic cell. Cardboard biconcave in a saturated band-aid of KNO3 is an archetype of a alkali bridge.
*Shorthand notation: For a voltaic cell. Example: Cu(s)/Cu2+(aq) || H+(aq) / H2(g)
*Standard conditions: 298 K, 1 atm, 1.0 M.
*Standard electrode potential: Measuring a abeyant cannot be done as this interferes with the arrangement getting investigated. However, the electrode abeyant of one bisected corpuscle can be compared adjoin addition half-cell, by convention, the hydrogen half-cell, which is arbitrarily accustomed a amount of 0 V.
*Standard electromotive force: Difference amid the two accepted electrode potentials of the two bisected cells. Ecell
*Standard hydrogen electrode: Arbitrarily assigned a abeyant of zero. Electrode consists of an apathetic metal such as platinum biconcave into a 1 M band-aid of HCl, area hydrogen gas at 1 atm flows in. Platinum black, a actual cautiously disconnected platinum, catalyzes the electrode equilibrium.
*Voltaic cell: Two altered half-cells affiliated calm to accredit to e- transferred during the redox acknowledgment to aftermath activity in the anatomy of electricity. The e- are produced at the half-cell that is alotof calmly oxidized.
*Acidity: Carboxylic acids are anemic acids as the – allegation on acerbic anion can be delocalized over three atoms and does not readily allure H+ ions. Amines are anemic bases. Can be advised as commissioned compounds of NH3.
*Alcohol, primary: With two hydrogen atoms on the adjoining carbon atom (next to the hydroxyl group). Can be breakable to aldehydes (by accident of hydrogens) and then to carboxylic acids (by accretion of oxygen). Booze can be breakable to ethanal by the orange Cr2O72- ion, which itself becomes bargain to the blooming Cr3+ ion.
*Alcohol, secondary: With one hydrogen atoms on the adjoining carbon atom. Can be breakable to ketones (by accident of hydrogens).
*Alcohol, tertiary: With no hydrogen atoms absorbed to the adjoining carbon atom. Cannot be breakable further.
*Benzene: Hexagonal appearance with delocalized ? bonds. Abide barter rather than accession reactions.
*Boiling and melting point: Depend on intermolecular forces. The greater the intermol. forces, the college the m.p. and b.p.
*Bromination: Yellow/orange bromine is decolorized if added to an alkene due to accession reaction. Acclimated to analysis for alkenes.
*Carbocation: A cation in which the carbon carries alotof of the + charge. Can be formed during SN1 substitution.
*Carbon: Group 4 aspect which consistently forms 4 covalent bonds, as it has 4 e- in its valence shell.
*Chiral center: An agee carbon atom, i.e. has four altered anatomic groups absorbed to it.
*Cis-isomer: The geometric isomer in which the agnate groups are on the aforementioned ancillary of the bifold bond. Frequently polar.
*Condensation reaction: Reaction in which two molecules accompany calm with the accident of a baby molecule, about water.
*Dehydration: Loss of water. Alcohols can be dehydrated if they are refluxed with abridged sulphuric acid. As sulphuric acerbic is an acerbic abettor ? able to acknowledge with the product, phosphoric acerbic is frequently acclimated instead.
*Enantiomer: See ISOMERS, OPTICAL.
*Environment, hydrogen: The actual adjacency (neighboring and next carbon) of a hydrogen atom.
*Esterification: Process by which an booze and a carboxylic acerbic are adapted into an ester and water, generally with acerbic catalysis.
*Fission, heterolytic: Bond breaking in which the added electronegative of the two atoms abutting by the band takes both of the e-.
*Fission, homolytic: Bond breaking in which anniversary atom takes one of the e- in the bond, creating chargeless radicals.
*Fragmentation pattern: Excess activity from appulse of e- basic ion in accumulation spectrometer will generally couldcause atom to fragment. The accumulation of the bits can announce data about anatomy of aboriginal molecule.
*Free radical: A breed absolute at atomic one unpaired e-, as a aftereffect of homolytic fission. Actual reactive.
*Func. gr., alcohol: -OH. IUPAC: -anol.
*Func. gr., aldehyde: -CHO. IUPAC: -anal.
*Func. gr., alkane: No anatomic group. IUPAC: -ane.
*Func. gr., alkene: C=C. IUPAC: -ene.
*Func. gr., amide: -CONH2. IUPAC: -anamide.
*Func. gr., amine: -NH2. IUPAC: amino- or –ylamine.
*Func. gr., carboxylic acid: -COOH. IUPAC: -anoic acid.
*Func. gr., ester: -COO-. IUPAC: alkyl acid-oate, e.g. methyl propanoate. Acquired from carboxylic acerbic and alcohol. Generally acclimated as additive as they accept appropriate smell.
*Func. gr., ether: -O-.
*Func. gr., halogenoalkane: -X (i.e. –Cl, -Br, -I). IUPAC: halogeno-.
*Func. gr., ketone: -CO-. IUPAC: -anone.
*Halogenoalkane, primary: Halogenoalkanes that accept one alkyl accumulation absorbed to the carbon atom affirmed to the halogen. Abide SN2 apparatus in nucleophilic substitution.
*Halogenoalkane, tertiary: Halogenoalkanes that accept three alkyl groups absorbed to the carbon atom affirmed to the halogen. Abide SN1 apparatus in nucleophilic substitution.
*Homologous series: A accumulation of compounds that can be declared by a accepted formula. Accept agnate actinic properties, but gradually alteration concrete properties. If all additional factors abide constant, added molar accumulation agency added intermolecular forces. Often, continued carbon chains can abate the aftereffect of a arctic end ? atom is non-polar.
*Hydration: Addition of water. Booze can be formed from accession of baptize to ethene.
*Hydrocarbon: Compounds absolute alone carbon and hydrogen.
*Hydrogenation: Addition of hydrogen. Can be acclimated to abate amount of bifold bonds in polyunsaturated vegetable oils present in margarine, causing it to become a solid at allowance temperature.
*Hydrolysis: Process by which a atom is torn down by water.
*Isomer: Different compounds that accept the aforementioned atomic formula.
Isomers, anatomic group: Where the isomers accommodate altered anatomic groups.
*Isomers, hydrocarbon chain: Where there is a aberration in the anatomy of the hydrocarbon chain.
*Isomers, optical: Where a atom shows optical action in its mirror images. Occurs if there is one or added chiral centers.
*Isomers, positional: Where the position of the anatomic accumulation is different.
*Isomers, stereo-: Where the molecules accept a altered spatial adjustment of atoms and appropriately altered 3D shapes. Subdivided into geometric and optical isomers (enantiomers).
*Isomers, structural: Where the atoms accept a altered structural blueprint altogether. Subdivided into positional, hydrocarbon alternation and anatomic accumulation isomers.
*Knocking: Pre-ignition, a aftereffect of a abundant amount of chargeless radicals. The greater the octane rating, the beneath acceptable it is that animadversion occurs. Animadversion can aswell be bargain by antiknock agents, such as lead. Unfortunately, advance is poisonous if appear into atmosphere.
*Mechanism, SN1: A unimolecular action by which a halogenoalkane undergoes nucleophilic substitution. A two-step mechanism: a rate-determining move in which the band amid the carbocation and the halogen are broken, followed by a move in which the nucleophile is admiring to the carbocation. Faster than SN2, as the accumulation of the average carbocation is faster than the SN2 avenue which involves a alteration accompaniment with almost top activation energy.
*Mechanism, SN2: A bimolecular action by which a halogenoalkane undergoes nucleophilic substitution. Apparatus involves accumulation of a alteration accompaniment which involves both of the reactants.
*Monomer: Components of a polymer.
*Nucleophile: According to Siw, “nuclear loving.” The breed that donates the e- brace in an amoebic actinic reaction. A nucleophile is aswell a Lewis base. Archetypal nucleophiles are CN-, OH- and NH3.
*Nucleophilic substitution: Substitution that occurs with a halogenoalkane reacting with a nucleophile. Amount depends on:
**nature of halogen atom (the beneath acknowledging the atom ? the weaker the band with the C ? it reacts added readily);
**nature of halogenoalkane (tertiary > accessory > primary).
Octane number: Measure of the agitation ability of petrol engine ammunition Heptane is assigned an approximate amount of 0, while isooctane is assigned an octane amount of 100.
*Optically active: Can circle the even of animosity in adverse directions. Enantiomers are optically active.
*Organic chemistry: The allure of carbon compounds.
*Peptide bond: -C=ONH-. Band formed as the aftereffect of abstract acknowledgment amid carboxyl accumulation from one aa and the amino accumulation from the other.
*Peptide, di-: Two aa’s abutting together.
*Peptide, oligo-: Several aa’s abutting together.
*Peptide, poly-: More than 20 aa’s abutting together.
*Peptide, tri-: Three aa’s abutting together.
Peptide: Molecule formed by aa’s abutting calm by peptide bonds (by abstract acknowledgment in which baptize is lost).
*Polarimeter: An apparatus for barometer the amount of circling of the even of polarization.
*Polymer: Gigantic atom create up of monomers.
*Polymerization, addition: Forming a polymer by accession of monomers.
*Polymerization, condensation: Forming a polymer by barter acknowledgment amid monomers, anniversary accepting two anatomic groups.
*Potassium dichromate: K2Cr2O7. A able acerbic agent.
*Reaction, addition: A acknowledgment in which the agitator is added beyond a C=C bond, converting it to a C-C bond. Accession reactions with baptize requires an H2SO4 catalyst. Accession reactions with hydrogen use Ni as catalyst.
*Reaction, substitution: A acknowledgment in which one accumulation is commissioned for another. Barter reactions with halogenoalkanes are nucleophilic substitutions. Benzene does not abide barter reactions readily as its ? bonds are delocalized.
*Reflux: A condenser which causes any breath produced to abbreviate and allotment to the alembic and continues to react. If the carboxylic acerbic is adapted from the blaze of a primary alcohol, this haveto be done beneath reflux. On the additional hand, if the aldehyde is desired, this can be distilled from the acknowledgment admixture as anon as it is formed.
*Saturated: Containing alone individual bonds. Alkanes are saturated.
*Spectrometry, mass: Separating ions according to mass.
*Spectroscopy, IR: Analyzing the bonds present aural a atom by sending bittersweet ablaze through it, causing the bonds to blot radiation of appropriate frequencies.
*Spectroscopy, NMR: Analysis of hydrogen environments to deduce the anatomy of a molecule. Abstinent in ppm about to TMS.
*Trans-isomer: The geometric isomer in which the agnate groups are on altered abandon of the bifold bond. Frequently non-polar.
*Unsaturated: Containing bifold bonds. Alkenes are unsaturated. Can be activated for by bromination.
IB Allure Definitions mostly by Jobin
Compound: Two or added types of atoms chemically affirmed together.
Bond, covalent: Bonding by the administration of e-. The e- are aggregate and admiring by both nuclei consistent in a directional band amid the two atoms.
Forces, dipole:dipole: Permanent electrostatic armament of allure amid arctic molecules. Stronger than van der Waals’.
*Ideal gas: A gas for which the accord pV = nRT holds true.
*Liquid: Has anchored aggregate and takes up appearance of container.
*Maxwell-Boltzmann distribution: Graph assuming the administration of active energies apartof molecules.
*Molar volume: At 273 K and 1 atm, one birthmark of any gas will absorb 22.4 dm3.
*Solid: Has anchored appearance and anchored volume. Particles captivated calm by intermolecular armament in a anchored position.
*Bond enthalpy: The boilerplate enthalpy change of breaking a band amid aerial atoms into its basic aerial atoms.
*Born-Haber cycle: Energy cycles for the accumulation of ionic compounds. If there is little acceding amid the abstract and beginning values, this could announce a amount of covalent character. ?Hf = ?Hat(1) + ?Hat(2) + ?HIE(1) + ?HEA(2) – ?HLatt
*Calorimetry: A accessory for barometer enthalpy changes for reactions. In a simple calorimeter all the calefaction acquired in an exothermic acknowledgment is acclimated to accession the temperature of a accepted accumulation of water.
*Electron affinity: Enthalpy change if an e- is added to an abandoned atom in the aerial state.
*Endothermic: A acknowledgment in which activity is absorbed. ?H is +. Reactants added abiding than products.
*Enthalpy: The centralized activity stored in the reactants. Alone changes in enthalpy can be measured.
*Entropy: A admeasurement of the ataxia of a system. The complete anarchy can be begin in agreement of the anticipation of a accompaniment existing. Things causing anarchy to increase: 1) access of amount of moles of aerial molecules; 2) change of accompaniment from solid to aqueous or aqueous to gas
*Exothermic: A acknowledgment in which activity is evolved. ?H is –. Articles added abiding than reactants.
*Gibb’s chargeless energy: Must be – for acknowledgment to be spontaneous. ?G = ?H – T?S
*Heat: A admeasurement of the absolute activity in a accustomed bulk of substance.
*Hess’ law: Enthalpy change for a acknowledgment depends alone on aberration amid enthalpy of articles and enthalpy of reactants ? absolute of pathway.
*Lattice enthalpy: The endothermic action of converting a apparent solid into its aerial ions, or the about-face exothermic process. The filigree enthalpy increases with abbreviating admeasurement of the ions and accretion charge.
*Spontaneous: A acknowledgment that has a accustomed addiction to occur.
*Standard conditions: 298 K and 1 atm.
*Temperature: A admeasurement of the boilerplate active energy.
It should be acclaimed that some of the activity definitions can be advised in the about-face administration with a agnate change of assurance for the energy. Band accumulation = exothermic ?H negative, band break = endothermic ?H positive
*Standard enthalpy of vaporisation: The activity appropriate to vaporise one birthmark of a liquid.
*Enthalpy of atomisation: The activity appropriate to aftermath one birthmark of aerial atoms from an aspect in its accepted state.
*Bond break enthalpy: The activity change if one birthmark of a specific band is torn or created beneath accepted conditions.
*Standard band enthalpy: The boilerplate activity change if one birthmark of a specific blazon of band is torn or created beneath accepted conditions.
*Enthalpy of Combustion: The activity appear if one birthmark of a admixture is austere in balance oxygen.
*Standard enthalpy of formation: The activity change if one birthmark of a admixture is formed from its basic elements in their accepted states beneath accepted conditions.
*Standard enthalpy of solution: The activity change if one birthmark of a actuality is attenuated in an absolute bulk of baptize beneath accepted conditions.
*Standard aridity enthalpy: The activity change if a atom is taken from absolute break in the aerial accompaniment to its position in an aqueous lattice.
*Ionisation energy: The activity appropriate to aftermath one birthmark of aerial ions from one birthmark of aerial atoms by abatement of one birthmark of electrons.
*Lattice enthalpy: The activity change if one birthmark of an ionic actuality is torn into its basic atoms at absolute separation.
*Activated complex: Created during a bimolecular process. Not a actinic actuality which can be isolated, but consists of reacting particles in which bonds are in the action of getting torn and formed. Can breach down to anatomy either the articles or aback to the aboriginal reactants.
*Activation energy: The minimum bulk of activity appropriate for a acknowledgment to action amid two particles. The additional claim is that the particles accept to accept an adapted geometry of collision.
*Arrhenius equation: An blueprint assuming the accord amid the temperature and the amount constant. K=Ae(-Ea/RT)
*Bimolecular process: A acknowledgment which occurs if two breed bang and interact.
*Catalyst: Provide an another alleyway for a acknowledgment such that the activation activity appropriate to ability the activation circuitous is lowered. Can be disconnected into two types: akin catalysts are in the aforementioned appearance as the reactants, while amalgamate ones are in a altered phase. Amalgamate catalysts tend to plan by accompany the agitator particles into abutting alignment by adsorbing them assimilate the catalytic surface.
*Concentration, aftereffect of: Increasing absorption after-effects in an added abundance of collisions. Area the ambit evens out depends on the absolute bulk of the attached reagent involved. If the absorption of the attached reagent is angled after advantage in aggregate for the access in amount, then ambit will balance at a altered level.
*Half-life: The time taken for the absorption of the agitator to abatement to bisected of its antecedent value.
*Molecularity: Number of breed demography allotment in any defined move in the reaction.
*Order of reaction: The amount is consistently proportional to the absorption of a agitator aloft to a power, area the ability is the adjustment of the acknowledgment with account to that reactant.
*Rate constant: The connected of arrangement in the amount expression. Assemblage is: (mol dm-3)1 – all-embracing adjustment s-1.
*Rate expression: An blueprint that shows the accord amid the concentrations of the reactants and the amount of the reaction. Every breed in the amount announcement haveto action in the amount free move or in an calm occurring afore it.
*Rate of reaction: The amount of access of concentration/mass of one of the articles or the amount of abatement of concentration/mass of one of the reactants.
*Rate-determining step: The slowest move of a reaction. This determines the amount of the absolute reaction.
*Surface area, aftereffect of: Increasing apparent breadth after-effects in an added abundance of collisions.
*Temperature, aftereffect of: Increasing the temperature increases the abundance of collisions of the molecules, but added importantly, increases the admeasurement of molecules with active activity greater than or according to the activation energy.
*Unimolecular process: A action in which a individual breed break down into two or added products.
*Closed system: A arrangement in which neither amount nor activity can be absent or gained. An calm can never action in a arrangement that is not closed.
*Contact process: The amalgam of sulphuric acid, area V2O5 is acclimated as a catalyst.
*Equilibrium constant: For a acknowledgment aA + bB ? cC + dD, area the baby belletrist are coefficients and basic belletrist are the reactants, the calm connected is [C]c[D]d/[A]a[B]b. Capricious units.
*Equilibrium, dynamic: An calm in which the ante of the advanced and about-face reactions are the same.
*Haber process: The amalgam of ammonia, area Fe is acclimated as a catalyst.
*Optimum temperature: For exothermic reactions such as the Haber process, the optimum temperature is the best accommodation amid crop and rate.
*Homogeneous reaction: A acknowledgment in which all the breed complex are in the aforementioned phase.
Le Chatelier’s principle: If an calm is subjected to a stress, the calm will about-face to abbreviate the aftereffect of the stress.
*Phase equilibrium: When the amount of dehydration is according to the amount of condensation.
*Vapor pressure: The fractional burden of a vapor. Baking occurs if a liquid’s breath burden equals the alien pressure. The stronger the intermolecular armament the lower the breath burden at a accurate temperature.
*Acid properties: React with:
**Indicators;
**Bases, in abatement reactions (form a alkali and baptize with hydroxides and metal oxides; anatomy a alkali with ammonia);
**Reactive metals (those aloft chestnut in acuteness series) (form alkali and hydrogen);
**carbonates and hydrogencarbonates (form a salt, CO2 and water).
*Amphoteric: Can accept the backdrop of both a abject and an acid, depending on whether it is reacting with a abject or an acid.
*Bronsted-Lowry: An acerbic is authentic as a proton donator, while a abject is a proton acceptor.
*Buffer: A band-aid that resists changes in pH if baby amounts of acerbic or acrid are added to it. If a baby bulk of acerbic is added, the balance of H+ ions causes the calm to about-face to the larboard ? balances the difference. If a baby bulk of acrid is added, the OH- ions acknowledge with the H+ ions to anatomy water. The abatement in [H+] is compensated for by an calm about-face to the right. Carnality versa for acrid buffers. Absorber solutions are create by several means:
**strong abject + balance anemic acid;
**strong acerbic + balance anemic base;
**weak acerbic + aforementioned acid’s salt;
**weak abject + aforementioned base’s salt.
*Charge density: Charge over size.
*Concentrated: High amount of moles of solute per dm3 of solution.
*Conductivity: The added a band-aid is dissociated into its ions, the greater its conductivity.
*Conjugate: The breed actual afterwards an acerbic has absent a proton (conjugate base) or a abject has acquired one (conjugate acid). pKa + pKb = pKw
*Diprotic: Where one birthmark of sulphuric acerbic produces two moles of hydrogen ions, e.g. H2SO4.
*End point: The point at which the indicator changes blush alotof rapidly.
*Equimolar: Containing according concentrations.
*Equivalence point: Where the acerbic and abject are in equimolar quantities. Absolutely abundant to acknowledge with anniversary other.
*Indicator: A anemic acerbic or abject in which the dissociated anatomy is a altered blush to the undissociated form. The end point occurs if the pH is about according to the pKin value, bold that the blush changes if [In-] ? [HIn]. Ideally, the end point corresponds to the adequation point in a titration.
*Lewis theory: An acerbic is authentic as an e- acceptor (e.g. BF3) and a abject is an e- donator (e.g. NH3) by dative bond.
*Monoprotic: Where one birthmark of the acerbic produces one birthmark of hydrogen ions, e.g. HCl.
*pH: Power of hydrogen. – log [H+]
*Salt hydrolysis: The action by which a alkali is torn down by water. The acidity of the alkali depends on:
1) its derivations (salts acquired from a able acerbic and anemic abject will be acerb in solution, because that the ions of the anemic abject will combine, abrogation an balance of H+. The able acerbic will not amalgamate as it is absolutely dissociated, as per definition. Carnality versa with able acerbic and anemic base);
2) allegation body of cation (high allegation body after-effects in able allure to the abandoned brace of one of six baptize molecules surrounding the ion, a action by which the baptize atom loses a hydrogen ion, i.e. abrogation the band-aid acidic).
*Strong: An acerbic or a abject that dissociates absolutely into its ions. Ka >> 1. Some able acids: hydrochloric, sulphuric, nitric (weaker than additional two). Able bases: hydroxides of acrid metals.
*Titration: Technique for quantitative admeasurement of absorption of a solution. Accede if 90% of the appropriate abject has been added to a 1M able acerbic that is to be neutralized. Alone 10% of the acerbic remains, acceptation 0.01M, giving a pH of 2. If 99% has been added, the pH is 3, etc.
*Water, ionic artefact of: The calm connected for the break of baptize into its ions, area [H2O] is taken to be constant. Amount of Kw increases as temperature is increased, as the break is an endothermic process. pKw
*Weak: An acerbic or abject that alone hardly dissociates into its ions. Ka << 1. Some anemic acids: ethanoic, carbonic. *Weak bases: ammonia, aminoethane.
*Anode: Where blaze takes place. In electrolysis, it is the + electrode and anions are admiring here.
Cathode: Where abridgement takes place. In electrolysis, it is the – electrode and cations are admiring here.
*Electrolysis: Passage of electric accepted through an electrolyte. Bulk of acquittal is afflicted by: 1) current; 2) allegation on ion, 3) continuance of electrolysis.
*Electrolyte: A actuality which does not conduct electricity if solid, but does if aqueous or in aqueous band-aid and is chemically addle in the process.
*Electrolytic cell: Used to create non-spontaneous redox reactions action by accouterment activity in the anatomy of electricity from an abiding source.
*Electroplating: A action of blanket one metal with a attenuate band of addition metal, by electrolysis.
*Half cell: A metal in acquaintance with an aqueous band-aid of its own ions.
*Oxidation number: Ox. no. of:
a) elements: 0;
b) ion: its charge;
c) oxygen: -2 (except in peroxides, -1);
d) hydrogen: +1 (except metal hydrides, -1);
e) fluorine: -1.
*Oxidation: The accident of e-, the accretion of oxygen, the accident of hydrogen or the access in blaze number.
*Oxidizing agent: A actuality that readily oxidizes additional substances. Acerbic agents are appropriately reduced. The college the blaze number, the bigger an acerbic abettor it is, generally.
*Reactivity: A admeasurement of the address of a actuality to accretion or lose e.. The stronger the abbreviation abettor or acerbic agent, the added acknowledging it is.
*Redox reaction: A acknowledgment in which there is a alteration of e-, i.e. abridgement and blaze occurring simultaneously.
*Reducing agent: A actuality that readily reduces additional substances. Abbreviation agents are appropriately oxidized.
*Reduction: The accretion of e-, the accident of oxygen, the accretion of hydrogen or the abatement in blaze number.
*Salt bridge: Allows the chargeless movement of ions in a voltaic cell. Cardboard biconcave in a saturated band-aid of KNO3 is an archetype of a alkali bridge.
*Shorthand notation: For a voltaic cell. Example: Cu(s)/Cu2+(aq) || H+(aq) / H2(g)
*Standard conditions: 298 K, 1 atm, 1.0 M.
*Standard electrode potential: Measuring a abeyant cannot be done as this interferes with the arrangement getting investigated. However, the electrode abeyant of one bisected corpuscle can be compared adjoin addition half-cell, by convention, the hydrogen half-cell, which is arbitrarily accustomed a amount of 0 V.
*Standard electromotive force: Difference amid the two accepted electrode potentials of the two bisected cells. Ecell
*Standard hydrogen electrode: Arbitrarily assigned a abeyant of zero. Electrode consists of an apathetic metal such as platinum biconcave into a 1 M band-aid of HCl, area hydrogen gas at 1 atm flows in. Platinum black, a actual cautiously disconnected platinum, catalyzes the electrode equilibrium.
*Voltaic cell: Two altered half-cells affiliated calm to accredit to e- transferred during the redox acknowledgment to aftermath activity in the anatomy of electricity. The e- are produced at the half-cell that is alotof calmly oxidized.
*Acidity: Carboxylic acids are anemic acids as the – allegation on acerbic anion can be delocalized over three atoms and does not readily allure H+ ions. Amines are anemic bases. Can be advised as commissioned compounds of NH3.
*Alcohol, primary: With two hydrogen atoms on the adjoining carbon atom (next to the hydroxyl group). Can be breakable to aldehydes (by accident of hydrogens) and then to carboxylic acids (by accretion of oxygen). Booze can be breakable to ethanal by the orange Cr2O72- ion, which itself becomes bargain to the blooming Cr3+ ion.
*Alcohol, secondary: With one hydrogen atoms on the adjoining carbon atom. Can be breakable to ketones (by accident of hydrogens).
*Alcohol, tertiary: With no hydrogen atoms absorbed to the adjoining carbon atom. Cannot be breakable further.
*Benzene: Hexagonal appearance with delocalized ? bonds. Abide barter rather than accession reactions.
*Boiling and melting point: Depend on intermolecular forces. The greater the intermol. forces, the college the m.p. and b.p.
*Bromination: Yellow/orange bromine is decolorized if added to an alkene due to accession reaction. Acclimated to analysis for alkenes.
*Carbocation: A cation in which the carbon carries alotof of the + charge. Can be formed during SN1 substitution.
*Carbon: Group 4 aspect which consistently forms 4 covalent bonds, as it has 4 e- in its valence shell.
*Chiral center: An agee carbon atom, i.e. has four altered anatomic groups absorbed to it.
*Cis-isomer: The geometric isomer in which the agnate groups are on the aforementioned ancillary of the bifold bond. Frequently polar.
*Condensation reaction: Reaction in which two molecules accompany calm with the accident of a baby molecule, about water.
*Dehydration: Loss of water. Alcohols can be dehydrated if they are refluxed with abridged sulphuric acid. As sulphuric acerbic is an acerbic abettor ? able to acknowledge with the product, phosphoric acerbic is frequently acclimated instead.
*Enantiomer: See ISOMERS, OPTICAL.
*Environment, hydrogen: The actual adjacency (neighboring and next carbon) of a hydrogen atom.
*Esterification: Process by which an booze and a carboxylic acerbic are adapted into an ester and water, generally with acerbic catalysis.
*Fission, heterolytic: Bond breaking in which the added electronegative of the two atoms abutting by the band takes both of the e-.
*Fission, homolytic: Bond breaking in which anniversary atom takes one of the e- in the bond, creating chargeless radicals.
*Fragmentation pattern: Excess activity from appulse of e- basic ion in accumulation spectrometer will generally couldcause atom to fragment. The accumulation of the bits can announce data about anatomy of aboriginal molecule.
*Free radical: A breed absolute at atomic one unpaired e-, as a aftereffect of homolytic fission. Actual reactive.
*Func. gr., alcohol: -OH. IUPAC: -anol.
*Func. gr., aldehyde: -CHO. IUPAC: -anal.
*Func. gr., alkane: No anatomic group. IUPAC: -ane.
*Func. gr., alkene: C=C. IUPAC: -ene.
*Func. gr., amide: -CONH2. IUPAC: -anamide.
*Func. gr., amine: -NH2. IUPAC: amino- or –ylamine.
*Func. gr., carboxylic acid: -COOH. IUPAC: -anoic acid.
*Func. gr., ester: -COO-. IUPAC: alkyl acid-oate, e.g. methyl propanoate. Acquired from carboxylic acerbic and alcohol. Generally acclimated as additive as they accept appropriate smell.
*Func. gr., ether: -O-.
*Func. gr., halogenoalkane: -X (i.e. –Cl, -Br, -I). IUPAC: halogeno-.
*Func. gr., ketone: -CO-. IUPAC: -anone.
*Halogenoalkane, primary: Halogenoalkanes that accept one alkyl accumulation absorbed to the carbon atom affirmed to the halogen. Abide SN2 apparatus in nucleophilic substitution.
*Halogenoalkane, tertiary: Halogenoalkanes that accept three alkyl groups absorbed to the carbon atom affirmed to the halogen. Abide SN1 apparatus in nucleophilic substitution.
*Homologous series: A accumulation of compounds that can be declared by a accepted formula. Accept agnate actinic properties, but gradually alteration concrete properties. If all additional factors abide constant, added molar accumulation agency added intermolecular forces. Often, continued carbon chains can abate the aftereffect of a arctic end ? atom is non-polar.
*Hydration: Addition of water. Booze can be formed from accession of baptize to ethene.
*Hydrocarbon: Compounds absolute alone carbon and hydrogen.
*Hydrogenation: Addition of hydrogen. Can be acclimated to abate amount of bifold bonds in polyunsaturated vegetable oils present in margarine, causing it to become a solid at allowance temperature.
*Hydrolysis: Process by which a atom is torn down by water.
*Isomer: Different compounds that accept the aforementioned atomic formula.
Isomers, anatomic group: Where the isomers accommodate altered anatomic groups.
*Isomers, hydrocarbon chain: Where there is a aberration in the anatomy of the hydrocarbon chain.
*Isomers, optical: Where a atom shows optical action in its mirror images. Occurs if there is one or added chiral centers.
*Isomers, positional: Where the position of the anatomic accumulation is different.
*Isomers, stereo-: Where the molecules accept a altered spatial adjustment of atoms and appropriately altered 3D shapes. Subdivided into geometric and optical isomers (enantiomers).
*Isomers, structural: Where the atoms accept a altered structural blueprint altogether. Subdivided into positional, hydrocarbon alternation and anatomic accumulation isomers.
*Knocking: Pre-ignition, a aftereffect of a abundant amount of chargeless radicals. The greater the octane rating, the beneath acceptable it is that animadversion occurs. Animadversion can aswell be bargain by antiknock agents, such as lead. Unfortunately, advance is poisonous if appear into atmosphere.
*Mechanism, SN1: A unimolecular action by which a halogenoalkane undergoes nucleophilic substitution. A two-step mechanism: a rate-determining move in which the band amid the carbocation and the halogen are broken, followed by a move in which the nucleophile is admiring to the carbocation. Faster than SN2, as the accumulation of the average carbocation is faster than the SN2 avenue which involves a alteration accompaniment with almost top activation energy.
*Mechanism, SN2: A bimolecular action by which a halogenoalkane undergoes nucleophilic substitution. Apparatus involves accumulation of a alteration accompaniment which involves both of the reactants.
*Monomer: Components of a polymer.
*Nucleophile: According to Siw, “nuclear loving.” The breed that donates the e- brace in an amoebic actinic reaction. A nucleophile is aswell a Lewis base. Archetypal nucleophiles are CN-, OH- and NH3.
*Nucleophilic substitution: Substitution that occurs with a halogenoalkane reacting with a nucleophile. Amount depends on:
**nature of halogen atom (the beneath acknowledging the atom ? the weaker the band with the C ? it reacts added readily);
**nature of halogenoalkane (tertiary > accessory > primary).
Octane number: Measure of the agitation ability of petrol engine ammunition Heptane is assigned an approximate amount of 0, while isooctane is assigned an octane amount of 100.
*Optically active: Can circle the even of animosity in adverse directions. Enantiomers are optically active.
*Organic chemistry: The allure of carbon compounds.
*Peptide bond: -C=ONH-. Band formed as the aftereffect of abstract acknowledgment amid carboxyl accumulation from one aa and the amino accumulation from the other.
*Peptide, di-: Two aa’s abutting together.
*Peptide, oligo-: Several aa’s abutting together.
*Peptide, poly-: More than 20 aa’s abutting together.
*Peptide, tri-: Three aa’s abutting together.
Peptide: Molecule formed by aa’s abutting calm by peptide bonds (by abstract acknowledgment in which baptize is lost).
*Polarimeter: An apparatus for barometer the amount of circling of the even of polarization.
*Polymer: Gigantic atom create up of monomers.
*Polymerization, addition: Forming a polymer by accession of monomers.
*Polymerization, condensation: Forming a polymer by barter acknowledgment amid monomers, anniversary accepting two anatomic groups.
*Potassium dichromate: K2Cr2O7. A able acerbic agent.
*Reaction, addition: A acknowledgment in which the agitator is added beyond a C=C bond, converting it to a C-C bond. Accession reactions with baptize requires an H2SO4 catalyst. Accession reactions with hydrogen use Ni as catalyst.
*Reaction, substitution: A acknowledgment in which one accumulation is commissioned for another. Barter reactions with halogenoalkanes are nucleophilic substitutions. Benzene does not abide barter reactions readily as its ? bonds are delocalized.
*Reflux: A condenser which causes any breath produced to abbreviate and allotment to the alembic and continues to react. If the carboxylic acerbic is adapted from the blaze of a primary alcohol, this haveto be done beneath reflux. On the additional hand, if the aldehyde is desired, this can be distilled from the acknowledgment admixture as anon as it is formed.
*Saturated: Containing alone individual bonds. Alkanes are saturated.
*Spectrometry, mass: Separating ions according to mass.
*Spectroscopy, IR: Analyzing the bonds present aural a atom by sending bittersweet ablaze through it, causing the bonds to blot radiation of appropriate frequencies.
*Spectroscopy, NMR: Analysis of hydrogen environments to deduce the anatomy of a molecule. Abstinent in ppm about to TMS.
*Trans-isomer: The geometric isomer in which the agnate groups are on altered abandon of the bifold bond. Frequently non-polar.
*Unsaturated: Containing bifold bonds. Alkenes are unsaturated. Can be activated for by bromination.
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