CHEMISTRY A2 EQUATIONS

nucleophillic substitution with aqueous AgNO3

(CH₃)₂CHBr + H₂O -->(CH₃)₂CHOH +H⁺(aq) + Br⁻(aq) dissolved in ethanol

nucleophillic substitution with KCN in ethanolic solution

(CH₃)₂CHBr + KCN -->(CH₃)₂CHCN+K⁺(aq) + Br⁻(aq) HEAT UNDER REFLUX product called propanenitrile

nucelophillic substitution with ammonia

(CH₃)₂CHBr + NH₃ -->(CH₃)₂CHNH₂ +NH₄⁺(aq) + Br⁻(aq) CONCENTRATED AMMONIA sealed tube, Heat product called ethyl amine

reduction of a carboxylic acid

(nucleophilic addition) lithium aluminium hydride in dry ether

grignard reagent + carbonyl compounds

1. carbonyl compound + grignard reagent 2.then dilute acid

acylation of amines

1.RCOCl + R'NH₂ → HCl + RCONHR' R'NH₂ + HCl → R'NH₃⁺Cl⁻ violent reaction concentrated aqueous solution of amine produces solid white mixture of products

phenol + bromine water

2,4,6-tribromophenol - insoluble in water and ppt out of the mixture. smells of antiseptic. orange colour decolorizes.

tollens reagent with aldehyde + heat

2Ag(NH₃)₂(aq) + RCHO(aq) + 3OH-(aq) →2Ag(s) + RCOO⁻(aq) + 4NH₃ + 2H₂0 colourless →silver mirror (use water bath no flame)

catalytic converters using platinum rubidium rhodium

2CO + 2NO --> 2CO2 + N2

group 2 nitrates

2Ca(NO₃)₂ → 2CaO(s) + 4NO₂(g) + O₂(g)

Equilibrium +6 Cr

2CrO₄²⁻(aq) + 2H⁺(aq) ⇌ Cr₂O₇²⁻ (aq) + H₂O(aq) add acid to chromate to form dichromate yellow → orange

oxidation of Cr3+

2Cr³⁺(aq) + 10OH⁻(aq) + 3H₂O₂(aq) → 2CrO₄⁻(aq) + 8H₂O(l) + alkaline conditions

Reduction of Cr3+

2Cr³⁺(aq) + Zn(s) → Zn²⁺(aq) + 2Cr²⁺(aq) inert atomsphere Cr²+ is so unstable that it oxidises straight back to to Cr³+

combustion of benzene

2C₆H₆ + 15O₂ → 12CO₂ + 6H₂O smoky flame due to high c:h atoms

group 1 nitrates

2KNO₃(s) → 2KNO₂(s) + O₂(g) except lithium 4LiNO₃ → Li₂O + 4NO₂ + O₂

chlorine reaction with cold sodium hydroxide (aq)

2NaOH(aq) + Cl₂(aq) --> NaClO(aq) + NaCl(aq) + H₂O(l)

Iodoalkanes

3C₃H₇OH + PI₃ ---> 3C₃H₇I +H₃PO₃ RTP red phosphorous

chlorine reaction with hot sodium hydroxide (aq)

6NaOH(aq) + 3Cl₂(aq) --> NaClO₃(aq) + 5NaCl(aq) + 3H₂O(l)

catalytic reformation

C6H14 ---> C6H6 + 4H₂ Pt 500 degrees High pressure

complete combustion

CH4 + 2O2 → 2H2O + CO2

oxidation of Potassium Manganate VII of an alkene

CH₂=CH₂ + H₂O + MnO4⁻ ---> CH₂(OH)CH₂OH ethane-1,2- diol purple to colourless

aqueous alkaline nucleophillic substitution reagent NaOH or KOH

CH₃CH₂Br + NaOH(aq) --> CH₃CH₂OH + NaBr(aq) heat under reflux in aqueous solution

ELIMINATION of haloalkanes

CH₃CH₂BrCH₃ + NaOH(ethanol) --> CH₃CH=CH₂ + NaBr(aq) + H₂O heat under reflux with conc solution of NaOH in ethanol

neutralisation of amines

CH₃CH₂NH₂ + HCl → CH₃CH₂NH₃⁺Cl⁻ forms ethylammonium chloride (ammonium salt)

amines dissolve in water

CH₃CH₂NH₂ + H₂O → CH₃CH₂NH₃⁺ + OH⁻ FORMS ALKALINE SOLUTION

hydrolysis of a nitrile

CH₃CN + 2H₂O + HCl → CH₃COOH + NH₄Cl reflux with dilute hydrochloric acid

iodination of propanone

CH₃COCH₃(aq) + I₂(aq) → CH₃COCH₂I(aq) + H⁺(aq) + I⁻(aq) You can monitor the reaction by adding NaHCO₃ at regular intervals and titrating this with sodium thiosulphate to work out concentration

acyl chloride + amines RTP

CH₃COCl + CH₃NH₂ → CH₃CNHCH₃ + HCl Violent reaction producing N- amide

acyl chloride + alcohol RTP

CH₃COCl + CH₃OH → CH₃COOCH3 + HCl vigorous reaction MISTY FUMES GIVEN OFF

acyl chloride + water

CH₃COCl + H₂O → CH₃COOH + HCl vigorous reaction with cold water MISTY FUMES GIVEN OFF

acyl chloride + concentrated ammonia RTP

CH₃COCl + NH₃ → CH₃CONH₂ + HCl violent reaction produces and amide

group 2 carbonates

CaCO₃(s) → CaO(s) + CO₂(g)

disproportionation of chlorine with water

Cl₂ (g)+ H₂O(l) --> HCl(aq) + HClO(aq)

aldehyde with acidified dichromate

Cr₂O₇²⁻ + 14H⁺ +6e⁻ → 2Cr³⁺ + 7H₂O orange →green

reduction of dichromate

Cr₂O₇²⁻(aq) + 14H⁺(aq) + 3Zn(s) → 3Zn²⁺(aq) + 2Cr³⁺(aq) + 7H₂O(l) zinc + dilute acid orange → green

Copper(II) +ammonia

Cu(H₂O)₆]²⁺(aq) + 2NH₃(aq) →[Cu(OH)₂(H₂O)₄](s) + 2NH₄⁺(aq) pale blue →blue ppt

Hydrogenation

C₂H₄ + H₂ --> C₂H₆(g) 150°C finely divided nickel catalyst making magerine and fats

alcohols made from steam

C₂H₄ + H₂O → CH₃CH₂OH (phosphoric acid catalyst and H₂O is steam ) 60 atm 300°C

how to make chloroalkanes by substitution

C₃H₇OH(l) + PCl₅(l) --> C₃H₇Cl(l) + POCl₃(l) + HCl(g) RTP

reducing a nitro compound

C₆H₅NO₂ + 6[H] → C₆H₅NH₂ + 2H₂O tin metal conc HCl reflux add naoah to get aromatic amine

benzene + bromine electrophilic substitution

C₆H₆ + Br₂ → C₆H₅Br + HBr room temperature halogen carrier (AlCl₃ or FeBr₃ or Fe)

Friedel-Crafts Alkylation

C₆H₆ + R-X → C₆H₅R + HX AlCl₃ catalyst

Friedel-Crafts Acylation

C₆H₆ + RCOCl → C₆H₅COR + HCl AlCl₃ catalyst

nitration of benzene

HNO₃ + H₂SO₄ → H₂NO₃⁺ + HSO₄⁻ H₂NO₃⁺ → NO₂⁺ + H₂O warm benzene with conc nitric acid and conc sulphuric acid catalyst mononitration <55⁰C polynitration >55⁰C

Hydrogen halides with water

HX(aq) + H₂O (l) --> H₃O⁺ + X⁻

iodine clock reaction

H₂O₂(aq) + 2I⁻(aq) + 2H⁺(aq) → 2H₂O(l) + I₂(aq) 2S₂O₃²⁻(aq) + I₂(aq) → S₄O₆²⁻(aq) + 2I⁻(aq) starch as indicator when thiosulphate is used up

Bromoalkanes

H₂SO₄(50% conc) + KBr --> HBr + KHSO₄ HBr +C₃H₇OH(l) --> C₃H₇Br(l) + H₂O

reduction of an aldehyde

LialH₄ in dry ether acts as a reducing agent

Magnesium with steam

Mg(s) + H₂0 ---> MgO + H₂

Magnesium with cold water

Mg(s) + H₂O ---> Mg(OH)2 + H₂

Hydrogen halides with ammonia

NH₃(g) + HCL(g) --> NH₄Cl (s)

bromide with sulphuric acid

NaBr(s) + H2SO4(l) ==> NaHSO4(s) + HBr(g) 2HBr(g) + H2SO4(l) ==> Br2(g) + SO2(g) + 2H2O(l)

chloride with sulphuric acid

NaCl + H2SO4 --> NaHSO4 + HCl

iodide with sulphuric acid

NaI(s) + H2SO4(l) ==> NaHSO4(s) + HI(g) 2HI(g) + H2SO4(l) ==> I2(g) + SO2(g) + 2H2O(l) 6HI(g) + SO2 ==> 3I2(g/s) + H2S(g) + 2H2O(l)

grignard reagent + CO2

R-MgBr + O=C=O → RCOOH +MgBrCl bubble CO₂ through grignard reagent in dry ether 2. add dilute acid eg HCl

production of grignard reagents

R-X → RMgX refluxing a halogenoalkane with magnesium in dry ether

fehlings solution with aldehyde + heat

RCHO(aq) + 2Cu²⁺ + 5OH⁻→RCOO⁻(aq) + Cu₂O(s) + 3H₂O(l) Blue→brick red ppt

carboxylic acid + phosphorous (V) chloride

RCOOH + PCl₅ → RCOCl + POCl₃ + HCl you get an acyl chloride

chlorination of alchols

ROH + HCl → RCl + H₂O fastest for tertiary rather than primary

chromium(III) ions + ammonia `

[Cr(H₂O)₆]³⁺(aq) + 3NH₃(aq) → [Cr(OH)₃(H₂O)₃](s) + 3NH₄⁺(aq) green → grey-green ppt

chromium(III) ions + NaOH

[Cr(H₂O)₆]³⁺(aq) + 3OH⁻(aq) → [Cr(OH)₃(H₂O)₃](s) + 3H₂O(l) green → grey-green ppt

chromium hydroxide ppt +excess ammonia

[Cr(OH)₃(H₂O)₃](s) + 6NH₃(aq) → [Cr(NH₃)₆](aq) + 3OH⁻(aq) + 3H₂O(l) ligand exchange reaction grey-green ppt → purple solution

chromium hydroxide ppt + excess NaOH

[Cr(OH)₃(H₂O)₃](s)+ 3OH⁻(aq) → [Cr(OH)₆]³⁻(aq) + 3H₂O(l) grey-green ppt → dark green solution H₂O ligands deprotonate

amines + copper ions

[Cu(H₂O)₆]²⁺ → [Cu(OH)₂(H₂O)₄] → [Cu(CH₃(CH₂)₃NH₂)₄(H₂O)₂]²⁺ addition of butylamine 1. pale blue ppt 2.deep blue solution

Copper(II) +NaOH

[Cu(H₂O)₆]²⁺(aq) + 2OH⁻(aq) →[Cu(OH)₂(H₂O)₄](s) + 2H₂O pale blue →blue ppt

Copper(II) +excess ammonia

[Cu(OH)₂(H₂O)₄](s) + 4NH₃(aq) → [Cu(NH₃)₄(H₂O)₄](s) +4H₂O + 2OH- ligand exchange blue ppt → deep blue solution

Iron (II) + Ammonia

[Fe(H₂O)₆]²⁺(aq) + 2NH₃(aq) → [Fe(OH)₂(H₂O)₄](s) + 2NH₄⁺(aq) pale green → green ppt(darkens on standing)

iron (II) + NaOH

[Fe(H₂O)₆]²⁺(aq) + 2OH⁻(aq) → [Fe(OH)₂(H₂O)₄](s) + 2H₂O(l) pale green → green ppt(darkens on standing)

test for tertiary alcohols

acidified potassium dichromate no change

test for primary alcohols

acidified potassium dichromate turns green from orange +H₂O

test for secondary alcohols

acidified potassium dichromate turns green from orange +H₂O

fuel cell in alkaline coniditions

anode = 2H₂ + 4OH⁻ → 4H₂O + 4e⁻ cathode = O₂ + 2H₂O + 4e⁻ --> 4OH-

fuel cell in acidic conditions

anode = H₂ → 2H⁺ + 2e⁻ cathode= ¹/₂O₂ + 2H⁺ + 2e⁻ →H2O

dehydrating agents

cacl2 MgSO₄

2,4-dinitrophnylhydrazine +dissolved in methanol and concentrated sulphuric acid

forms a bright orange ppt with carbonyl compounds

esterification (condensation)

heat with an concentrated acid catalyst reversible reaction therefore distill asap product mixed with NaCO₃ to react with carboxylic acid.

h3c-c-0 iodoform and methyl carbonyl

heat with iodine in presence of alkali RCOCH₃ + 3I₂ + 4OH⁻ → RCOO⁻ + CHI₃ + 3I⁻ + 3H₂Oi Yellow ppt antiseptic smell

catalytic hydrogenation of nitriles

high temperature high pressure metal catalyst Pt or Ni hydrogen gas

hydrolysis of polypeptides

hot aqueous 6 mol dm⁻³ HCl heated under reflux for 24 hours final mixture neutralised with a base

incomplete combustion

hydrocarbon + oxygen → carbon monoxide + (carbon) + water + (carbon dioxide)

amines + halogenoalkanes

like the ammonia as nitrogen has lone pair

OAlCl3- friedel-crafts

makes alcohols

hydrogen cyanide + carbonyl

nucleophilic addition (acidified potassium cyanide as HCN is toxic)

amino acid polymerisation

peptide link formed polypetide = protien

elimination alcohols can be dehydrated

phosphoric acid used

dicarboxylic acids + diamines

polyamide

catalytic cracking

produces alot fo aromatic compounds using a zeoltlite catalyst (hydrated aluminosilicate) at aslight pressure and high temperature of 450°C

thermal cracking

takes place at high temperatures and high pressure. (up to 1000°C 70 atm) this proudces alot of alkenes

group 1 carbonates

thermally stable except lithium Li₂CO₃(s) → Li₂O(s) +CO₂(g)

reduction of a nitrile

use LiAlH₄ in dry ether followed by dilute acid

acid hydrolysis of ester

use alot of dilute acid this is reversible

base hydrolysis of ester

use dilute alkali