Copy of Teknikjawabstpm782010

8/9/2019 Copy of Teknikjawabstpm782010

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ANSWERINGANSWERING

TECHNIQUETECHNIQUE

STPMSTPM

CHEMISTRYCHEMISTRYWong Lai SiengWong Lai Sieng

SMK ROSLI DHOBY, SIBUSMK ROSLI DHOBY, SIBU


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Ununbium 112Ununbium 112

superheavy elementsuperheavy element

zinc [30] + lead [82] = Ununbium[112]zinc [30] + lead [82] = Ununbium[112]


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ELEMENTELEMENT: ?????: ?????

SYMBOLSYMBOL: Wo: Wo

DISCOVERERDISCOVERER:???:???ATOMIC MASSATOMIC MASS: accepted as 55 but: accepted as 55 but

known to vary from 45 to 225known to vary from 45 to 225

OCCURRENCEOCCURRENCE: found in large quantities: found in large quantitiesin urban areas, with trace elements inin urban areas, with trace elements inoutlying regions.outlying regions.

PHYSICAL PROPERTIESPHYSICAL PROPERTIES: boils at: boils atabsolutely nothing, freezes for noabsolutely nothing, freezes for noapparent reason. Melts if given specialapparent reason. Melts if given specialtreatment, bitter if used incorrectly.treatment, bitter if used incorrectly.


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CHEMICAL PROPERTIESCHEMICAL PROPERTIES: affinity to gold, silver,: affinity to gold, silver,platinum and all precious stones. Theplatinum and all precious stones. The

most powerful money reducing agent knownmost powerful money reducing agent knownto man.to man.

COMMON USECOMMON USE: highly ornamental, especially in: highly ornamental, especially insports cars. Can be a very effective cleaningsports cars. Can be a very effective cleaning

agent.agent.HAZARDSHAZARDS: highly dangerous except in: highly dangerous except in

experienced hands. Illegal to possess moreexperienced hands. Illegal to possess morethan one, although several can be maintainedthan one, although several can be maintained

at different locations as long as specimens doat different locations as long as specimens donot come into direct contact with each othernot come into direct contact with each other

Quote from book 3 Prisons Diary by JefferyQuote from book 3 Prisons Diary by JefferyArcherArcher


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TIPS FOR STPM EXAMSTIPS FOR STPM EXAMS

MEMORISE WITH UNDERSTANDINGMEMORISE WITH UNDERSTANDING[ FORMULAE, RULES, PRINCIPLES &[ FORMULAE, RULES, PRINCIPLES &DEFINITIONS]DEFINITIONS]

ANALYSE QUESTIONS CAREFULLY &ANALYSE QUESTIONS CAREFULLY &CORRECTLYCORRECTLY

APPLY CONCEPTS LEARNT INAPPLY CONCEPTS LEARNT IN

DIFFERENT SITUATIONSDIFFERENT SITUATIONSALWAYS ASK THE QUESTION WHATALWAYS ASK THE QUESTION WHAT

IF ?IF ?


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962 PHYSICAL CHEMISTRY962 PHYSICAL CHEMISTRY

Paper 2Paper 2Data booklet providedData booklet provided1. Periodic table with proton number,1. Periodic table with proton number,

relative atomic mass, symbol of elementsrelative atomic mass, symbol of elements

2. Important values, constants & standards2. Important values, constants & standards3. First to fourth ionisation energies of3. First to fourth ionisation energies of

selected elementsselected elements

4. Standard electrode & reduction4. Standard electrode & reductionpotentialspotentials

NOTE: molar volume at 25NOTE: molar volume at 25ooC is 24.4dmC is 24.4dm33

NOT 24 dmNOT 24 dm33


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Chapter 12: phase equilibriumChapter 12: phase equilibrium

1. Raoults Law1. Raoults Law

Partial vapour pressure of A in solution, pPartial vapour pressure of A in solution, pAA = x= xAA x px pAAoo

Where xWhere xAA = mole fraction of A; p= mole fraction of A; pAAoo = vapour pressure of pure A= vapour pressure of pure A

2. For immiscible liquids, p2. For immiscible liquids, ptotaltotal = p= pAAoo + p+ pBB

oo

3. Partition coefficient, K =3. Partition coefficient, K = concentration of X in solvent Aconcentration of X in solvent A == [X][X]AA

concentration of X in solvent B [X]concentration of X in solvent B [X]BB

4. For steam distillation,4. For steam distillation, mmAA == ppAA x Mx MAA mmH2OH2O ppH2OH2O x Mx MH2OH2O

Where mWhere mAA = mass of A in the distillate, M= mass of A in the distillate, MAA= relative molecular mass of A= relative molecular mass of A

mmH2OH2O = mass of water in the distillate, M= mass of water in the distillate, MH2OH2O= relative molecular mass of water = 18.0= relative molecular mass of water = 18.0 ppAA = vapour pressure of pure A at the boiling point of the system= vapour pressure of pure A at the boiling point of the system

5. R5. Rff == distance travelled by the componentdistance travelled by the component

distance travelled by the solvent frontdistance travelled by the solvent front


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allotropesallotropesTin exists as two allotropes. White tin isTin exists as two allotropes. White tin is

stable above 13stable above 13ooC. When Kept belowC. When Kept below1313ooC for a long time, it changes intoC for a long time, it changes intogrey tin.grey tin.

Which of the following is true for theWhich of the following is true for theallotropes?allotropes?

A.A. They have the same bond lengthThey have the same bond lengthB.B. They have the same isotopic compostionThey have the same isotopic compostion

C.C. They have the same electricalThey have the same electricalconductivtiyconductivtiy

D.D. They have the same enthalpy ofThey have the same enthalpy of

reaction with oxygenreaction with oxygen


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Which of the following reactions willWhich of the following reactions will

increase in yield when the pressure isincrease in yield when the pressure isdecreased at a constant temperature?decreased at a constant temperature?

A. NA. N22(g) + 3H(g) + 3H22(g) 2NH(g) 2NH33(g)(g)B. HB. H22(g) + CO(g) + CO22(g) H(g) H22O(g) + CO(g)O(g) + CO(g)

C. 2SOC. 2SO22(g) + O(g) + O22(g) 2SO(g) 2SO33(g)(g)

D. HD. H22S(g) + IS(g) + I22(s) 2HI(g) + S(s)(s) 2HI(g) + S(s)


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Le Chatelier PrincipleLe Chatelier Principle


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Define standard enthalpy change ofDefine standard enthalpy change of

formationformationHeat liberated when one mole of theHeat liberated when one mole of the

substance is formed from its gaseoussubstance is formed from its gaseousatoms under standard conditionsatoms under standard conditions --inaccurateinaccurate

HeatHeat evolved or absorbedevolved or absorbed whenwhen oneonemolemole of the substance is formed fromof the substance is formed from

itsits elementselements under standardunder standardconditionsconditions


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Writing thermochemical equationWriting thermochemical equation

Standard enthalpy change of formation.Standard enthalpy change of formation.

3C(s) + 4H3C(s) + 4H22(g)(g) CC33HH88(g)(g) HHff ==

1 mole1 mole

3C(diamond) + 4 H3C(diamond) + 4 H22(g)(g) CC33HH88(g) ((g) (XX))HHff

==


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Which thermochemical equation is correct?Which thermochemical equation is correct?

Standard enthalpy change of atomisation.Standard enthalpy change of atomisation.

11.. II22(s)(s) I(g)I(g) HHff == --106.0kJmol106.0kJmol--11

1 mole1 mole

22..1/21/2 II22(s)(s) I(g)I(g) HHff = +106.0kJmol= +106.0kJmol--1133.I.I22(s)(s) 2I(g)2I(g) HHff

= +106.0kJmol= +106.0kJmol--11

44. I (s) I (g). I (s) I (g) HfHf = +106.0kJmol= +106.0kJmol--11

Thermochemical equation,Thermochemical equation, H must beH must bewritten on the right of the equation.written on the right of the equation.

H : + /H : + / -- sign shownsign shown


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v

Lewis structure/ Dot and crossLewis structure/ Dot and cross

diagramsdiagramsAlClAlCl33

Cl

yy

yy yy

y

y y

y

Al

ClClyy

y

y

y

y

OR

Cl

ClCl

yy

yy

yy

yy

yy

yy

yy

yyyy

y

y

y y

y

y

Alyy

y

v

v

v

Al AlCl

Cl Cl Cl

Cl

Clv

v

v v

v

y

y

y

y

y

y

y y

y y

y

yy yy

y

y

yyy

(X) (X)


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Structural formula of AlStructural formula of Al22ClCl66

Cl Cl Cl

AlAl AlAl

ClCl ClCl ClCl

is the structural formula correct?is the structural formula correct?


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Differentiate atoms, molecules, ions,Differentiate atoms, molecules, ions,

compounds, elements & substancescompounds, elements & substances

(wrong usage of terminology)(wrong usage of terminology)

e.g. The ability ofe.g. The ability ofan atoman atom to distort orto distort orpolarize the valence electron cloud ofpolarize the valence electron cloud ofan anion depends on its charge andan anion depends on its charge and

size. If the charge density ofsize. If the charge density ofthetheatomatom is high, the electron cloud ofis high, the electron cloud ofthe anion will be distorted more.the anion will be distorted more.


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Inaccurate answer from calculationsInaccurate answer from calculations

Example 1:Example 1:

An acidic solution with concentrationAn acidic solution with concentration

0.03moldm0.03moldm--33 contains 8.1 x 10contains 8.1 x 10--44 moldmmoldm--33

hydrogen ions. Calculate the pH of thehydrogen ions. Calculate the pH of theacidic solution.acidic solution.

pH =pH = --loglog1010[H[H++]]


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pH =pH = --loglog1010[H[H++]]

== --loglog1010 8.1 x 108.1 x 10--44

= 3.091514981 ( X )= 3.091514981 ( X )

=3.1( 2 significant figures)=3.1( 2 significant figures)

WRONG SUBSTITUTIONOF DATAWRONG SUBSTITUTIONOF DATA

Example 2:Given pressure 50 kPa.Example 2:Given pressure 50 kPa.

When it is substituted into equationWhen it is substituted into equationpV=nRTpV=nRT

P =(i) 50 x 10P =(i) 50 x 1033 PaPa (ii)5 x 10(ii)5 x 1044 PaPa

(iii)(iii) 50000 Pa50000 Pa

(iv)(iv) 5.0 x 105.0 x 1044

PaPa


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WRONG SUBSTITUTIONOF DATAWRONG SUBSTITUTIONOF DATA

Example 2:Given pressure p=50.0 kPa,Example 2:Given pressure p=50.0 kPa,V= 2.00dmV= 2.00dm33, T=25, T=25ooC, R=8.31JmolC, R=8.31Jmol--11KK--11

Calculate the value of n.Calculate the value of n.

When it is substituted into equationWhen it is substituted into equation

pV=nRTpV=nRT

P =(i) 50.0 x 10P =(i) 50.0 x 1033 PaPa (ii)5 x 10(ii)5 x 1044 PaPa

(iii)(iii)50000 Pa (iv)50000 Pa (iv) 5.0 x 105.0 x 1044 PaPa

(a)(a)V=2 x 10V=2 x 10--33 mm33 (b) 0.002 m(b) 0.002 m33

(c) 2.00 x 10(c) 2.00 x 10--33 mm33


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For reversible reactionFor reversible reaction

A (g) + B (g)A (g) + B (g) C (g) + D (g)C (g) + D (g)

KKcc== or Kor K

pp==

A (aq) + B (aq)A (aq) + B (aq) C (aq) + D (aq)C (aq) + D (aq)

KKcc or Kor Kpp ????????

]][[

]][[

BA

DC

PP

PP

BA

DC


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INACCURATE STATEMENTSINACCURATE STATEMENTS

(i) Rate of reaction becomes faster(i) Rate of reaction becomes faster(ii)Thermal(ii)Thermal decompositiondecomposition of nitrate of groupof nitrate of group

2 elements increases down the group.2 elements increases down the group.

Physical statesPhysical states of reactants and products areof reactants and products are

required in the balanced equations forrequired in the balanced equations forinorganic chemistry and physical chemistryinorganic chemistry and physical chemistry

(electrochemistry , thermochemistry)(electrochemistry , thermochemistry)


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HalfHalf--equationequation

(i)Mg(i)Mg MgMg2+2+ + 2e+ 2e--

(ii)Mg(ii)Mg 2e2e-- MgMg2+2+ (X)(X)

(iii)O(iii)O22-- 2e2e-- O (X)O (X)(iv)2Cl(iv)2Cl-- ClCl22 + 2e+ 2e

--

(v)4Cl(v)4Cl-- 2Cl2Cl22 + 4e+ 4e-- (X)(X)


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FORMULA OF IONS PRODUCED INMASSFORMULA OF IONS PRODUCED INMASSSPECTROMETERSPECTROMETER

e.g1.e.g1. write the formulae of ions producedwrite the formulae of ions producedwhen Hwhen H22O is analysed in massO is analysed in massspectrometer.spectrometer.

HH++

(( ))O

HO

H--

(( ) H) H22++

(( )O

)O++

(( ))

e.g2. CH33Br

C++ (( )) H++ (( )) CH33++ (( )) Br-- (( ))

HH33++ (( ))


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FORMULA OF IONS PRODUCED INMASSFORMULA OF IONS PRODUCED INMASSSPECTROMETERSPECTROMETER

e.g1.e.g1. write the formulae of ions producedwrite the formulae of ions producedwhen Hwhen H22O is analysed in massO is analysed in massspectrometer.spectrometer.

HH++

(( ))O

HO

H--

((XX ) H) H22++

((XX )O

)O++

(( ))

e.g2. CH33Br

C++ (( )) H++ (( )) CH33++ (( )) Br-- ((XX ))

HH33++ ((XX ))


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Dehydrating agent :Dehydrating agent :

calcium chloride (x)calcium chloride (x)anhydrousanhydrous calcium chloride (calcium chloride ())

sulphuric acid (x)sulphuric acid (x)

concentratedconcentrated sulphuric acid (sulphuric acid ())e.g. HCOOH CO + He.g. HCOOH CO + H22OO

Conditions of reaction:?Conditions of reaction:?


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Catalyst :Catalyst :aluminium chloride (x)aluminium chloride (x)anhydrous aluminium chloride ()anhydrous aluminium chloride ()

Benzene + chlorine chlorobenzene +HClBenzene + chlorine chlorobenzene +HCl


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ESTER

ACID +

ALCOHOLS

SALT +

ALCOHOLS

2ALCOHOLS

ACID +

ALCOHOLS

ACID

CHLORIDE

+ ALCOHOLS

ACID CHLORIDE

+ PHENOLS

AMIDE +

ALCOHOLS


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IODOFORMTESTIODOFORMTEST

ALCOHOLS

H

C-OH

CH3

ALDEHYDES

C=O

CH3

KETONES

C=O

CH3


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OH

1.+ H2

2. + Cl2/ Br2

3. + HNO3

1.+ Na

2.+ NaOH(aq)

3.CH3COCl /(CH3CO)2O


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Types of reactionsTypes of reactions

FunctionalFunctional

groupgroup

--C=CC=C-- C=OC=O CC--OO--HH --CC--XX BenzeneBenzene

& methyl& methyl

benzenebenzene

AttackingAttackingspeciesspecies

Type ofType ofreactionreaction

1. Electrophilic addition 2. electrophilic substitution

3. nucleophilic addition 4.Nucleophilic substitution

Attacking spesies: a) electrophiles b) nucleophiles

TYPEOFREACTION:


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AldehydesAldehydes

ketonesketones

1. + HCN

2. + [O]

3. + Tollens

4. + Fehling

[aliphatic only]

5.Reduction 1

o

alcohols

6.Condensation

7. Iodoform [CH3-C=O

Group only ]

1. + HCN

2.

3.

4.

5.Reduction 2oalcohols

6.Condensation

7. Iodoform[CH3-C=O

Group only ]

[O] + 1o alcohols [O] + 2o alcohols


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ORGANIC CHEMISTRYORGANIC CHEMISTRY

ALLALL the reactants and products havethe reactants and products have

to be written (NOT

the organicto be written (NOT

the organicproductsproducts

only )only ) UNLESSUNLESS question requiresquestion requiresthe conversion of one compound tothe conversion of one compound toanotheranother


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Examples :Examples :

CHCH33CHCH22O

H CHO

H CH22=CH=CH22 (x)(x)CHCH33CHCH22OHOH -- HH22O CHO CH22=CH=CH22 (x)(x)

CHCH33CHCH22OH CHOH CH22=CH=CH22 + H+ H22O (O ())

ClCl

OH + ClOH + Cl22 Cl OHCl OH

ClCl(x)(x)

- H20


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Test for Haloalkanes:Test for Haloalkanes:

use NaOH followed by addition ofuse NaOH followed by addition ofAgNOAgNO33 solution.solution.

CHCH33CHCH22Cl + NaOH CHCl + NaOH CH33CHCH22OH + NaClOH + NaCl

NaCl + AgNONaCl + AgNO33 AgCl + NaNOAgCl + NaNO33

white precipitatewhite precipitate

CHCH33CHCH22Cl + AgNOCl + AgNO33 CHCH33CHCH22NONO33 + AgCl+ AgCl

(X)(X)


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Tollens reagentTollens reagent : use [ Ag(NH: use [ Ag(NH33))22]]++

NOTNOT

AgAg22O

or AgO

or Ag++

CHCH33CHO + AgCHO + Ag22OO CH CH33COOH + 2AgCOOH + 2Ag (X)(X)

CHCH33CHO + 2[Ag(NHCHO + 2[Ag(NH33))22]]++ + OH+ OH--

CHCH33COOCOO-- + 2Ag + 2NH+ 2Ag + 2NH44++ + 2NH+ 2NH33


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Chemical test to distinguish between 2Chemical test to distinguish between 2

organic compounds,organic compounds,example : Butanexample : Butan--11--ol & butanol & butan--22--ololreagent : Ireagent : I22 (aq) + NaOH(aq)(aq) + NaOH(aq)condition : warmcondition : warmobservations:Butanobservations:Butan--11--ol: no changesol: no changes

: no reaction (x): no reaction (x)ButanButan--22--ol: yellow precipitate isol: yellow precipitate is

produced ()produced ()CHICHI33 is produced (X)is produced (X)


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Equation:Equation:

For butanFor butan--22--ololCHCH3CH(OH)CHCH(OH)CH2CHCH3 + 6NaOH + 4I+ 6NaOH + 4I2CHICHI3 + CH+ CH3CHCH2COONa + 5HCOONa + 5H2O + 5NaIO + 5NaI


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Suggest with the help of equation howSuggest with the help of equation how11--bromopropane could be converted tobromopropane could be converted to

11--aminopropane [3]aminopropane [3]

Reagent:Reagent:excessexcess concentrated NHconcentrated NH3

solutionsolutionConditions: heated in a sealed tubeConditions: heated in a sealed tube

alcohol as solventalcohol as solvent

Equation: CHEquation: CH3CHCH2CHCH2Br + 2NHBr + 2NH3CHCH3CHCH2CHCH2NHNH2 ++ NHNH4BrBr

[HBr] X[HBr] X


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Suggest the structure formula for theSuggest the structure formula for thecompound A. Explain the reactionscompound A. Explain the reactions

involved with the help of equations.involved with the help of equations. A, CA, C7HH8O, burns with a smoky flame. A isO, burns with a smoky flame. A is

only slightly soluble in water, but veryonly slightly soluble in water, but verysoluble in sodium hydroxide solution.soluble in sodium hydroxide solution.

[5][5]


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A burns with smoky flame as % of carbonA burns with smoky flame as % of carbonis high.is high. [1][1]

Ratio of C: H is about 1, benzene ring isRatio of C: H is about 1, benzene ring ispresent.present. [1][1]

A is very soluble in NaOH as it is acidic.A is very soluble in NaOH as it is acidic.This implies that phenol group isThis implies that phenol group ispresent.[1]present.[1]

Structure of A: CHStructure of A: CH3-- --OH [1]OH [1]

CHCH3-- --OH + NaOH CHOH + NaOH CH3-- --ONaONa

+ H+ H2O

[1]O

[1]


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Phenol, CPhenol, C66HH55OH is a weak organic acid.OH is a weak organic acid.When 0.385g phenol is dissolved inWhen 0.385g phenol is dissolved in

2.00 dm2.00 dm33 of water at 25of water at 25ooC, pH of theC, pH of thesolution obtained is 6.29.solution obtained is 6.29. [6][6]

(a) calculate the dissociation constant(a) calculate the dissociation constant

KKaa of phenol at 25of phenol at 25oo

C.C.CC66HH55OH COH C66HH55OO-- + H+ H++ [1][1]

KKaa = [ C= [ C66HH55OO--][H][H++]] [1][1][C[C66HH55OH]OH]


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pH = 6.29 (given)pH = 6.29 (given)

pH =pH = --loglog1010 [H[H++]]

[H[H++]= [C]= [C66HH55OO--] = 5.13 x 10] = 5.13 x 10--77 moldmmoldm--33 [1][1]

[ phenol] = 0.385 = 2.05 x 10[ phenol] = 0.385 = 2.05 x 10 --33 [1][1]

94.0 x 2.0094.0 x 2.00

Substitute into formula of KSubstitute into formula of Kaa

KKaa = ( 5.13 x 10= ( 5.13 x 10--77 ))22 [1][1] = 1.28 x 10= 1.28 x 10--1010

2.05 x 102.05 x 10--33 moldmmoldm--33

[1][1]


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write the scheme of reactions for thewrite the scheme of reactions for thefollowing conversions:following conversions:

1.1.

Br

NO2

Br +

NO2 NO2

Br

38% 62%

2.


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Structural formula for nitrobenzeneStructural formula for nitrobenzene

CC6HH5NONO2

(X)(X)

( )( )NO2


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2. At which of the carbon atoms in the2. At which of the carbon atoms in themolecule below is electrophilic attackmolecule below is electrophilic attackmost likely?most likely?

C O CH2CH2CH3

O

A

B

C D E


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Importance of stating physical stateImportance of stating physical state

Reaction of carboxylic acid withReaction of carboxylic acid withsodium carbonatesodium carbonate solutionsolution toto

liberate Carbon dioxide.liberate Carbon dioxide.SolidSolid sodium carbonate added tosodium carbonate added to

pure ethanoic acid, any reaction?pure ethanoic acid, any reaction?


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Write the electronic configuration ofWrite the electronic configuration ofvalencevalence electronselectrons of phosphorusof phosphorus( proton number = 15)( proton number = 15)

3s3s223p3p33 ( )3s3s223p3pXX

113p3pYY113p3pZZ

11 ()

2.8.5 (x)2.8.5 (x)1s1s222s2s222p2p663s3s223p3p33 (x)(x)[Ne]3s[Ne]3s223p3p33 (X)(X)


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Write the electronic configuration ofWrite the electronic configuration ofsodiumsodium--24 isotope.24 isotope.

1s1s22

2s2s22

2p2p66

3s3s11

( )( ) [Ne]3s[Ne]3s11 (X)(X)

2.8.8.6 (X)2.8.8.6 (X)

1s1s22

2s2s22

2p2p66

3s3s22

3p3p66

3d3d44

4s4s22

(X)(X)


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NameName the compound: PbClthe compound: PbCl44

Lead chloride (x)Lead chloride (x)

Lead(II) chloride (X)Lead(II) chloride (X)

Plumbum(IV)chloride (X)Plumbum(IV)chloride (X)Lead(IV) chloride (Lead(IV) chloride ())


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Name the compound: CuName the compound: Cu22OO

Copper oxide (x)Copper oxide (x)

Copper(II) oxide (x)Copper(II) oxide (x)kuprum(I) oxide (x)kuprum(I) oxide (x)

Copper (I) oxide (Copper (I) oxide ())


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Name the compound: CaSOName the compound: CaSO44

Calsium(II)sulphate (X)Calsium(II)sulphate (X)Calcium sulphate (Calcium sulphate ())


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Naming of complex ionNaming of complex ion

[Cr(NH[Cr(NH33))55Cl]Cl]2+2+Which of the following is correct?Which of the following is correct?1.Pentaaminechlorochromium(III)1.Pentaaminechlorochromium(III)

2.Pentaamminechlorochromium(II)2.Pentaamminechlorochromium(II)3.Pentaamminechlorochromium(III)3.Pentaamminechlorochromium(III)For amine CHFor amine CH33NHNH22

Which of the following is correct?Which of the following is correct?1.Methylammine1.Methylammine2.Methylamine2.Methylamine


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Structural formula of [Cr(NHStructural formula of [Cr(NH33))55Cl]Cl]2+2+

2+2+

NHNH33HH33NN NHNH33

CrCr

HH33NN NHNH33ClCl

Charge has to be shownCharge has to be shown


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Structural formula of [Co(NHStructural formula of [Co(NH33))33ClCl33]]

NHNH33HH33NN ClCl

CoCo

HH33NN ClCl

ClCl

isomer Facisomer Fac

isomer cis (X)isomer cis (X)


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Structural formula of [Co(NHStructural formula of [Co(NH33))33Cl3]Cl3]

ClCl

ClCl NHNH33CoCo

HH33NN NHNH33ClCl

isomer Merisomer Mer

isomer trans (X)isomer trans (X)


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WRONGGERERAL STATEMENTSWRONGGERERAL STATEMENTS

(i)(i) ALLALL group 1 elements are metalsgroup 1 elements are metals

(ii)(ii) ONLYONLY the compounds of transitionthe compounds of transitionelements are colouredelements are coloured

(iii)(iii) ONLYONLY the transition elements showthe transition elements showvariable oxidation states.variable oxidation states.


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State the changes in oxidation statesState the changes in oxidation statesof chlorine when chlorine reacts withof chlorine when chlorine reacts with

cold & dilute NaOHcold & dilute NaOH..

From 0 to +1 andFrom 0 to +1 and --1 (correct)1 (correct)

+1 and+1 and --1 (wrong)1 (wrong)

G t i l iG t i l i


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Geometrical isomersGeometrical isomers

inaccurate formulaeinaccurate formulaeExample: butExample: but--22--eneene

CHCH33 CHCH33 CHCH33 HH

C C C CC C C C

H H H CHH H H CH33


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Geometrical isomersGeometrical isomers

Example: butExample: but--22--eneeneCHCH33 CHCH33 CHCH33 HH

C=C C=CC=C C=C

H H H CHH H H CH33


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Inaccurate structural formula ofInaccurate structural formula ofoptical isomersoptical isomers

CC22HH55 CC22HH55

Br

Br CC

OH H

OOH H

OC

BrC

Br

CHCH33 CHCH33


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OPTICAL ISOMEROPTICAL ISOMER

CC22HH55 CC22HH55

CC CCBrBr OHOH HOHO BrBr

CHCH33 CHCH33


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GEOMETRICAL ISOMERGEOMETRICAL ISOMER

Example: Pt(NHExample: Pt(NH33))22ClCl22

NHNH33 Cl NHCl NH33 NHNH33

Pt PtPt Pt

ClCl NHNH33 Cl ClCl Cl

Trans- isomer Cis-isomer


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INSTRUCTIONAL CUE (KATAINSTRUCTIONAL CUE (KATATUGAS)TUGAS)

1.1. NameName2.2. Draw on diagram/indicate on graphDraw on diagram/indicate on graph3.3. State the differenceState the difference4.4. IdentifyIdentify5.5. DetermineDetermine6.6. CalculateCalculate7.7. SuggestSuggest8.8. explainexplain


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9. What do you observe9. What do you observe

10. What is meant by10. What is meant by

11. Draw a labelled diagram11. Draw a labelled diagram

12. Sketch a graph12. Sketch a graph

13. Desribe the properties of ethanoic13. Desribe the properties of ethanoicacid as a Bronstedacid as a Bronsted--Lowry acid.Lowry acid.

14. State what happens/ the change/14. State what happens/ the change/one chemicalone chemical

15. Arrange in ascending order15. Arrange in ascending order

16.Predict the shape16.Predict the shape


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THE WOODCUTTER & THE AXETHE WOODCUTTER & THE AXE

Many years ago, at Sipitang in SabahMany years ago, at Sipitang in Sabahthere was a very strong and skilledthere was a very strong and skilledwoodcutter who asked for a job with awoodcutter who asked for a job with atimber merchanttimber merchant

He got the job with a good salary andHe got the job with a good salary anddecent work conditions.And so, thedecent work conditions.And so, thewoodcutter was determined to do hiswoodcutter was determined to do his

best for the boss.

His boss gave him an

best for the boss.

His boss gave him an

axe and on his first day, the woodcutteraxe and on his first day, the woodcuttercut down 15 trees. The boss wascut down 15 trees. The boss waspleased and said: Well done, goodpleased and said: Well done, good

work!work!


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Highly motivated, the woodcutterHighly motivated, the woodcuttertried harder the next day, buttried harder the next day, but

could only fell 13 trees. The thirdcould only fell 13 trees. The thirdday, he tried even harder, butday, he tried even harder, butonly 11 trees were choppedonly 11 trees were chopped

down.down.Day after day, he tried harder butDay after day, he tried harder but

he cut down fewer trees. I musthe cut down fewer trees. I must

be losin

g my stren

gth, thebe losin

g my stren

gth, thewoodcutter thought. Hewoodcutter thought. Heapologised to the boss, claimingapologised to the boss, claiminghe could not understand why.he could not understand why.

When was the last time youWhen was the last time you


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When was the last time youWhen was the last time yousharpened your axe? the bosssharpened your axe? the bossasked. Sharpen? I had no timeasked. Sharpen? I had no timeto sharpen my axe. I have beento sharpen my axe. I have beentoo busy cutting down trees,too busy cutting down trees,said the woodcutter.said the woodcutter.

He sharpened his axe andHe sharpened his axe andimmediately was back to 15immediately was back to 15trees a day. Since then, hetrees a day. Since then, he

begins the day by sharpening hisbegins the day by sharpening hisaxe.axe.


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The woodcutter does needThe woodcutter does needdowntime to rest, but it is notdowntime to rest, but it is not

sharpening the axe. Thesharpening the axe. Thewoodcutter only becomes morewoodcutter only becomes moreproductive by sharpening hisproductive by sharpening hisblade, analysing newblade, analysing newwoodcutting techniques,woodcutting techniques,exercising to become stronger,exercising to become stronger,and learning from otherand learning from other

woodcutters.woodcutters.


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THANKTHANK

YOUYOU


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THE ENDTHE END

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