organic chemistry and definition. scanned,

8/4/2019 organic chemistry and definition. scanned,

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2 HalogenoalkanesHeat with aqueous ethanolic silver nitrate.(a) Chloroalkane: White precipitate(b) Bromoalkane: Cream precipitate(c) Iodoalkane: Yellow precipitateR-X + H20 +Ag" -- R-OH + H+ +AgX(s)

3 BenzeneHeated slowly with a mixture of concentrated nitric acid and concentratedsulphuric acid. Pour the products into cold water :A layer of yellow oil isobserved. N02 +H20+HNO, -

4 The -OH groupAdd solid phosphorus(V) chloride (Room temperature):White fumes given off.R-OH + PCl5 -- RCI + POCl3 + HCl(g)RCOOH + PCl5 -- RCOCI + POCl3 + HCI(g)5 The carbonyl group (aldehyde and ketone)Add 2,4-dinitrophenylhydrazine (Room temperature):

An orange precipitate is formed.N02 N02

~C = 0 + H2N -NH---@-N02 - ~C =N -NH---@- N02 + H206 Aldehydes

(a) Heat with Fehling's solution: A brown precipitate is formed.RCHO + 2Cu2+ + 50H- -- RCOO- + 3H20 + Cu20(s)

(b) Heat with Tollen's reagent: A silver mirror is formed.RCHO + 2[Ag(NH3)l + 20Er ~ RCOO- + 2Ag(s) + 3NH3 + 2H 20 + N H /

7 Carboxylic acidsAdd aqueous sodium carbonate (Room temperature) : Effervescence.2RCOOH + Na2C03 -- 2RCOONa + H20 + CO2

8 The benzoate ion(a) Dissolve the salt in water followed by dilute sulphuric acid:A white precipitate is formed.CsH5COO- + H+ -- CSH5COOH(s)

(b) Add aqueous irontl ll) chloride (Room temperature):A buff precipitate is formed.3CsH5COO- + Fe3+ -- (CsH5COO)3Fe(s)

9 Primary aminesWarmed with aqueous nitric(III) acid (a mixture of NaN02 and HCI):Effervescence is observed.RNH2 + HN02 -.>0 ROH +H20+ N2

10 AmidesWarmed with aqueous sodium hydroxide:Ammonia gas (which turns moist red litmus blue) liberated.RCONH2 + NaOH -- RCOpNa + NH3

Testing of ~halogenoalkanes withethanolic silver nitrate~ :

Testing of benzenes .(lwith concentrated acids "...:..................................... :

Testing of -OH group ~with PCls :. . . . . . - :

Testing of carbonyl Q -group with .2,4-dinitrophenylhydrazine:.................................. :

Testing of aldehydes ~with Fehling and Tollen's :reagents

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . =

Testing of carboxylic ~acids with sodiumcarbonate

-!l- , :

Testing for benzoate -(fions with(a) sulphuric acid(b) iron(ll l) chloride............................... - ....:

Tes~ing for primary . ( ! jarrunes with aqueous :nitric acid. . . . . . :

Testing for amides with ~aqueous sodium :hydroxide :

-of " :


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~ Testing for acyl chloride. with

(a) water(b) aqueous silver nitrate

: ~

~ Testing for phenols with: (a) bromine water. (b) aqueous ion: ....

~ Testing for phenylamines: with bromine water......................................

~Testing for methyl: alcohols or methyl

carbonyl compounds withalkaline iodine solution

: ..

~ Testing for ethanoate ion: with aqueous iron(lll)

chloride: ..~ Testing for ethanedioic: acid and ethanedioate

ions with acidifiedpotassium manganate(VII)

: ~~ Testing for methanoic: acid with aqueous

mercury{lI) chloride.................................

~ Testing for alkyl benzene: with acidified potassiummanganate(VII)

: ....

11 Acyl chloride(a) Add a little water (Room temperature): White fumes given off.

RCOCI + H20 -. RCOOH + HCI(g)(b) Add aqueous silver nitrate: White precipitate formed immediately.RCOCI + H20 +Ag+ - RCOOH +AgCl(s) + H+12 Phenols

(a) Add bromine water (Room temperature): White precipitate formed.O H- r w s r~ +3H",Sr

(b) Add aqueous iron(lII) chloride (Room temperature):Purple solution formed.

3C6H50H + Fe3+ - (C6H50)3Fe13 PhenylaminesAdd bromine water (Room temperature): White precipitate formed.

-14 The CHa-CH-R and CHa-C-R groupsI I I

OH 0Heat with a solution of iodine in aqueous sodium hydroxide:Yellow precipitate formed.

CHa-CH-R + 412+ 6NaOH - RCOONa + 5Nal + 5H20 + CHI3(s)IOH

CHrC-R + 312+ 4NaOH -. RCOONa + 3Nal + 3H20 + CHI3(s)IIo15 The ethanoate ion, CHaCOO-

Add aqueous irorufll) chloride (Room temperature) : A reddish-brownsolution formed.

3CH3COO- + FeCl3 -... (CH3COO)3Fe(aq) + 3Cr16 Ethanedioic acid, H2C204 or the ethanedioate ions, C20i-.Add acidified potassium manganate(VII) then warm the mixture: The

purple colour of potassium manganate(VII) is decolourized on warming.2Mn04- + 5C20l- + 16R+ - 2Mn2++ 10C02 + 8H20

17 Methanoic acid HCOOH.Warm with aqueous mercuryrll) chloride. A white precipitate is formed.

RCOOH + 2HgCl2 - Hg2C12+ CO2 + 2HCI18 AIkylbenzene

Warmed with acidified potassium manganate(VII): Purple colour ofpotassium manganate(VII) is decolourized.@- CR3 + 3[0] - @- COOH + H20


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Activation energy The minimum amount of energyrequired for a chemical reaction to occur.

Chromatography The technique to separate and toidentify the various components in a mixture.

Allotropy A phenomenon where an element can exist Common ion effect The shift in equilibrium caused byin more than one form. The different forms of an addition of a compound having an ion similar to one ofelement are called allotropes. Examples: Carbon ' the ions formed from the dissolved substances.(diamond, graphite); sulphur (rhombic and monoclinic);oxygen (oxygen and ozone, 03)'Anode The electrode where oxidation occurs.Arrhenius acid A chemical substance that dissociatesto form hydrogen ions H+when dissolved in water.Arrhenius base A chemical substance that dissociatesto form hydrogen ions H+ ions when dissolved in water.Autocatalysis A reaction where one of the productscan act as a catalyst for the reaction.Avogadro's law At constant temperature andpressure, all gases of equal volumes have the samenumber ofmoles.Avogadro's number The number of atoms in exactly12.0000 g ofcarbon-12 (6.023 x 1023 ).Azeotrope A mixture of liquids at a constant boilingpoint where the composition of the vapour is the sameas the composition of the liquid. The composition of theazeotrope remains unchanged on distillation.

Complex ion An ion containing a central metal cation or an atom that is bonded to a group of ligands by co-ordinate bonds.

Co-ordinate covalent bond A covalent bond whereboth the shared electrons are contributed by one of thetwo bonded atoms.Co-ordination number (complex ion) The number

of donor atoms that surround the central metal cation oratom in a complex ion. It is also equal to the number ofco-ordinate bonds formed by the central atom or ion

with ligands. [Note: It is not the number of ligands thatsurrounds the central ion or metal. Some polydentateligands can form more than one co-ordinate bond perligand with central ion or atom].Co-ordination number (solid) The number of atoms,molecules or ions surrounding a given particle in the

, solid lattice structure.Covalent bond The electrostatic attraction between

, two adjacent nuclei and the pair of electrons that are shared between them.Boiling point The temperature at which the vapour '

pressure of a liquid is equal to the atmospheric pressure. Critical point The temperature above which a gas will, not liquefy by increasing pressure only.Bond energy The amount of heat energy required tobreak a covalent bond in a gaseous molecule per mole of . Critical pressure The minimum pressure required to

the bond. bring about liquefaction of a gas at the criticalBoyle's law The volume of a fixed mass of gas at 'constant temperature is inversely proportional to itspressure.Bronsted-Lowry acid Aproton donor.,Bronsted-Lowry base A proton acceptor.Buffer capacity The amount of acid or base that needsto be added to a buffer solution to change its pH by oneunit.Buffer solution A solution where its pH does notchange significantly when a small amount of acid orbase is added to it.Catalyst A substance that alters the rate of a chemicalreaction without itself being altered.

temperature.Dalton's law of partial pressure The total pressure

of a mixture of gases that do not interact with oneanother is given by the sum of the partial pressures ofall the gases present.Dative bond A covalent bond where both the sharedelectrons are contributed by one of the two bondedatoms.

Degenerate orbitals Orbitals having the same energy.Degree of dissociation The fraction or percentage ofthe initial amount that has dissociated.Disproportionation A reaction in which the samesubstance is oxidised and reduced simultaneously.Distribution (partition) law A solute wil l distributeCatenation The ability of the atoms of an element to itself between two immiscible liquid solvents such thatform bonds with one another. the ratio of the concentrations of the solute in each

Cathode. The electrode where reduction occurs.Charles' law The volume of a fixed mass of gas atconstant pressure is directly proportional to its absolutetemperature.

solvent is a constant at constant temperature.The partition law is not obeyed for concentrated solutionor when the molecular species in the two solvents are

, not the same.


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Dynamic equilibrium The condition in which the rateof the forward reaction is equal to the rate of the reversereaction and the amount of substances remains constant.Effective collisions Collisions that results in theformation of products. Collisions in the correctorientation and with sufficient energy to overcome theactivation energyElectrochemical cell A device that converts chemicalenergy into electrical energy.Electrolysis The decomposition of an electrolyte byelectrical current.Electrolyte A substance that conducts electricityeither in the molten state or when dissolved in water.Electron affinity The heat change when a gaseousatom receives an electron, per mole of the atom.Electronegativity The relative strength of an atom toattract electrons in a covalent bond to which it is bonded.Enantiomers Compounds having the same molecularformula but are mirror images and are notsuperimposable.Enthalpy change of combustion The heat energyreleased when 1 mol of a substance is burnt completelyin excess of oxygen under standard conditions.Enthalpy change of formation The heat. change\ "hen 1 mol of a substance is formed from its elementsunder standard conditions.Enthalpy change of hydration The heat changewhen 1 mol of ions dissolve in water to form hydratedions under standard conditions.Enthalpy change of reaction The heat energychange that accompanies a chemical reaction.Enthalpy change of solution The heat change when1 . mol of a substance dissolves in water to form asolution ofinfinite dilution under standard conditions.Enthalpy change of vaporisation The heat energyrequired to vaporise 1 mol of a liquid at its boiling pointunder standard conditions.Enthalpy of atomisation The heat energy required toproduce 1 mol of free gaseous atoms from an elementunder standard conditions.Enthalpy of neutralisation The heat energy given offvhen 1 mol of water is formed from the reactionbetween an acid and a base under standard conditions.Equilibrium constant The ratio of the equilibriumconcentration of the products to the equilibriumconcentration of the reactants each raised to the powerof their respective stoichiometric coefficient.Faraday (F ) The amount of charge contained in 1 molof electrons.Faraday'S first law of electrolysis The amount ofsubstance produced during electrolysis is directlyproportional to the quantity of electricity that passesthrough the electrolyte.

Faraday's second law of electrolysis The relativeamount of substances produced by the same quantity ofelectricity is inversely proportional to the charge on theions.Fractional distillation A process for separating liquidcomponents in a liquid mixt.ure based on their differentboiling points.Free radical A neutral atom or molecule containing anunpaired electron. Free radicals are formed by thehemolytic fission of a covalent bond.Half-life The time taken for the amount of a substanceto decrease to half its initial value.Henry's law The solubility of a gas in a solvent ISdirectly proportional to its partial pressure.Hess's law The enthalpy change of a reaction ISindependent of its pathway.Hybridisation The combining of two or more non-equivalent atomic orbitals to form a set of equivalenthybrid orbitals.Hydrogen bond The electrostatic attraction between ahydrogen atom bonded to an atom of a veryelectronegative element (N, 0 or Fl and the lone pairelectrons of another very electronegative atom (N , 0 or F).Ideal gas A gas that obeys the ideal equation perfectlyunder all conditions.Ideal solution A solution that obeys Raoult's law.Ionic bond The electrostatic attraction betweenoppositely charged ions that are formed when electronsare transferred from one atom to another.Ionisation energy The minimum energy required toremove one electron from an isolated atom (or ion) in itsground state, per mole of the atom or ion.Isotopes Atoms of the same element (i.e. with thesame proton number) but with different nucleonnumber.Lattice energy The heat released when 1 mol of anionic solid is formed from its free gaseous ions understandard conditions.Le Chatelier's Principle When a system in dynamicequilibrium is subjected to a change, the position ofequilibrium will shift in the direction to nullify the effectof the change so that the equilibrium is reestablished.Lewis acid A subtance that accepts a lone pair ofelectrons from another substance.Lewis base A substance that donates a lone pair ofelectrons to another substance.Ligand An atom, a molecule or an ion that is bonded tothe metal atom or metal cation in a complex ion by co-ordinate bond.Matter Anything that has a mass and occupies space.Melting point The temperature at which the solidstate and liquid state are in equilibrium.


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Metallic bond The electrostatic attraction betweenmetal cations and the 'sea' of delocalised electrons in asolid lattice.Metalloid An element with properties of metal andnon-metal.Mole The amount of substance that contains the samenumber of elementary particles (atoms, molecules, ionsor electrons) as the number of atoms in exactly 12 g ofcarbon-12.Nucleon number Number of protons and neutrons inthe nucleus of an atom.Orbital A region in space where the probability offinding a particular electron is high (about 95% chance).Order of reaction The order of reaction is the sum ofthe powers to which the concentration of the reactantsare raised 11 1 an experimentally determined rateequation.

Rate = k[A] ' [B :P 'Order of reaction with respect to A is x.Order of reaction with respect to B is y.Overall order of reaction = x + y.Ostwald dilution law The degree of dissociation of aweak electrolyte is inversely proportional to itsconcentration. At infinite dilution (where concentrationapproaches zero), all weak electrolytes are fullydissociated.Overpotential The additional voltage required forelectrolysis to occur.Oxidation A process of electron loses.Oxidising agent A substance that can accept electronsfrom another substance.Partial pressure The pressure exerted by a gas, in amixture of gases, if that gas alone occupies the samevolume as the mixture at the same temperature.Pauli exclusion principle No two electrons in anatom can have the same four quantum numbers.Pi (n) bond A covalent bond formed by the sidewaysoverlapping of atomic orbitals (usually the p orbitals).The electron density of the bond is concentrated aboveand below the plane containing the nuclei of the twobonded atoms.Proton number The number of protons in the nucleusof an atom.Raoult's law The partial vapour pressure of a liquid,A, in a mixture of immiscible liquids, is given by theproduct of the vapour pressure of pure A and the molefraction ofA in the mixture, at the same temperature.

P A = XApOA

Rate-determining step The slowest step in asequence of steps that leads to the formation ofproducts. It is also the step with the highest activationenergy.Reducing agent A substance that donates electrons toanother substance.Reduction A process of electron gain.Relative atomic mass The mass of one atom of theelement relative to /2 times the mass of atom of carbon-12.Relative isotopic mass The mass of one atom of theisotope relative to 1 1 2 times the mass ofatom ofcarbon-12.Relative molecular mass The mass of one moleculeof the element or compound relative to : 2 times themass of atom of carbon-12.Screening effect The repulsion between electronicshells that are filled with electrons. It also refers to theeffect of shielding of the outermost electrons by innerelectrons from the pull of the nucleus.Sigma (a) bond A covalent bond formed by the end-to-end overlapping of atomic orbitals. The electron densityof the bond is concentrated in the region between thenuclei of the bonding atoms.Solubility product The product of the concentrationof the ions, in a saturated solution of a sparingly solublesalt, each raised to the power of its stoichiometriccoefficient.Standard electrode potential (EON) The potentialdifference between an electrode and its aqueous ions ofconcentration 1.0 mol dm=', relative to that of thestandard hydrogen electrode at 298 K and 101 kPa.Structural isomers Compounds having the samemolecular formula but different structural formula.Transition metals Elements that can form at leastone stable ion that has an incompletely filled d subshell.Triple point The temperature and pressure at whichthe solid, liquid and vapour phase of a substance canexist in equilibrium.van der Waals forces The intermolecular forces thatholds molecules of covalent compounds together in thesolid or liquid state.


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SUMMARY; E;:ctions of Benzene

cone. HN03 + cone. H2S04, 50C @-- N02C12, A12C16or Fe catalyst @-- CI

RCI + A12C16 - - @-- R@- RCOCI + AI2CI6 ~ @-- C-R- Il0Cone. H2SO4 ~ @-- S03H

H2, Ni catalyst - - 0;;=actions of Methylbenzene

CI2 + light @- CH2C1acidified KMn04, heat

@- COOH

acidified Cr203, heat@-CHO

CH3 CH3CI2 + AI2CI6 r C l and c 9 JH3

CI@- CH3 CH3 r R c 9 JRX + AI2CI6 and- - RCH3 CH3

concentrated H2SO4 r 5 0 3 H and c 9 JS03H

CH3 CH3cone. HN03 + cone. H2SO4 r N O ' and c 9 J

N02


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2U M M A R YReac tio ns o f H a l og enoa lk an e s

NaOH (aq ) ,ref lux

1---------+ R-NH2

~-------+ R-OHconcentrated

ammon ia

e tha no lic K CN1----------+ R-CN

ethanol ic R'COO

R e actio ns o f G rig na rd R e ag en ts

water~------------------~ RH

' " /C=C/ ' "

ketone,

methanal ,HCHO RCH 20H( pr im a ry a lc o ho l)

o th e r a ld eh y de s ,R 'CHO1----------------+ R - CH - R '

IOH(s eco nd a ry a le o :).

R 'R ' I"c = = 0 - . R - C - R 'R ' / I

OH( te rtia ry a lc oho l)

~ ------__ . R'COORe th an olic R 'O N aRX --4-----------+ R' -O-R

e tha no lic N aO H

N a in e the rI--------------__}I> R -Namagnes ium

in e th er

RMgX -

L------------+RCOOH1-----------------+RMgX

R eactions of Carboxylic Acids

R C O O H -

S U M M A R Y

NaOH

e le ctro po sitiv e m eta lI-------------------------~ R C O O - + H 2Na 2C0 3 or NaH C0 3f---------------------~ R C O O N a + ef fervescence (C 0 2)

R ' O H . concentra ted H 2S0 4- - - - - - - - - - - - - - - - ~ ~ R C O O R 'PClsI----------------------~ RCDe l + wh ite fu m es H C I

reduct ion


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SUMMARY~::sctions of Alcohol

sodium

ROH

a + 2R'COOH, concentrated H2SO4 R'COORPCls RCI + white fumes of HCI

KBr + concentrated H2SO4 RBrRed phosphorus + 12 RI

Excessof concentrated H2S04, 180 "C \ /C=C/ \concentrated H2S04, 140 0 c . Excessalcohol R-O-R

RCHOor RCOOH (for primary alcohol)Acidified KMn04 R-C-R (for secondary alcohol)

I I""'eactions of Phenol

sodium @- O-Na +H2NaOH @- O-Na+ H2O

RCOCI R-C-O -


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SUMMARY1 Reactions of Aldehydes

HCN

IR-C-H

NaHS03

2,4-dinitrophenylhydrazine

Acidified K2Cr207Tollen's reagentFehling's solution

ReductionZinc amalgam + HCI

OHI

R-C-CNIHOHI

R-C-SO;Na+IH

R -,C = N-NH/H

RCOOHRCOO- + silver mirrorRCOO- + reddish-brown precipitate of Cu20

2 Reactions of KetonesR'IHCN

--'" R-C-CNIOHR'

NaHS03

I. . . . . . R-C-SO;Na+IOH

N02R-C-R' 2,4-d initrophenyl hyd razi ne--'" R" -@-I C = N-NH R'/

Acidified KMn04, heat . . . . R'COOH + CO2 + H2OReduction

--'" R-CH-R'IOH

Zinc amalgam + HCI--'" RCH2R'


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SUMMARY ch1pter 30Reactions of Derivatives of Carboxylic Acids(a) Acid chloride

RCOOH + white fumes HCIoIIR-C-CI-

1--------------- RCOOR'R'OH

Concentrated NH31-------------=-----. RCONH2R'NH2L- RCONHR'

(b) EsterAcidic hydrolysis RCOOH + R'OH

RCOOR' -

Alkaline hydrolysis RCOONa + R'OHConcentrated NH3 RCONH2 + R'OH

Reduction, UAIH4 in ether

(c) AmideAcidic hydrolysis, heatr---------------_ RCOOH + NH4+

P4010(Dehydration)RCONH2 --+----__:___:_::__:__-.:;__-----=---- RCN

Alkaline hydrolysis, heat

Br2+ KOH~--------------- RNH2

Reduction

(d) Odours of some esters- - ~ - 1Ester Formula i Smell,

Methyl butanoate CH3CH2CH2COOCH3 ApplePenthylethanoate CH3COOCHzCH2CH2CH2CH3 BananaEthyl butanoate CH3CH3CH2COOC2Hs PineappleEthyl methanoate HCOOCzHs Rum


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Reactions of Alkylamines

S U M M A R Y

r-- .:....:H :_ 20 e-Oo RNH/ + owd i l u t e a c i d , W RNH3+

ROH + e f f e r v e s c e n c e (N2)RNH2~~ ~HN~O~2 ___L___ ~R_'C_O_C_I e-Oo R'CONHR

Reactions of Phenylamines

@-NH/

~_:_H.:..:.N.:....:O:....:2::...'h-e-at-----------..._@-OH+efferveSCenCe(N2)

RCOCI RCONH --@L _ : : b : _ : _ r o = - f f i : _ : _ _ : _ : _ : _ i. : . . . . : e : _ w _ a t _ e _ r ~ . . . . Wh i t e p re ci p it a te ,

Reactions of Benzene Diazonium ionH20 @-OH

_ .. @-I

@-CI

. . . . @-CN

@-N=N -@- OH

KI{aq)

CuCiJHCI

CuCN/KCN

(Q)- OH/NaOH

organic chemistry and definition. scanned,

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