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Formative Assessment Manual for Teachers Metals and Non-Metals - Chapter 3

c. Whatisthebrownakysubstance?

d. WhatarethecommonvalenciesshownbymetalM?

Suggested Remediation:

Somestudentsmaynditdifculttoremembervariousreactionsandpropertiesof

metals, their compoundsandgases evolved during reactions ofthe carbonates and

sulphideoreswithdiluteacids.Theymaybeencouragedtotabulatevariousreactions

ofmetalsingeneralformandbefamiliarwithallthereactions.

Revisitingchapter1ChemicalReactionsandEquationsmayberequiredforstudents

whonditdifculttowritebalancedchemicalreactions.

Attentionofthestudentsmaybedrawntowardscategorisingthereactionsintovarious

typesstudiedinchapter1.

Metals and Non-metals Chapter 3

Assessment Technique:MultipleChoiceQuestionsBasedWorksheet

Objectives:Toenablestudentsto-

Recallvariousphysicalandchemicalpropertiesofmetalsandnon-metals.

DrawcorrelationbetweentheoxideofanelementandpHofitsaqueoussolution.

Recallreactivityseriesofmetalstopredicttheproductsofareaction.

Applytheconceptualknowledgetodailyusesoftheelements.

Task: Individual

Procedure:

ThestudentsmaybegiventhefollowingMCQbasedworksheetaftertheteaching-learningofthe

completeunitMetalsandNon-metalstostrengthentheconcepts.

Assessment Parameters:Eachofthefollowingquestionsmaybeassessedgivingequalweightage

of1marktoeachcorrectanswer.

Student Worksheet: Time: 30 minutes

Choosethemostcurrentineachofthefollowing:

1. Ailthefollowingmaterialsshowpropertyofmalleabilityexcept

a. Iron b. Graphite c. Aluminium d. Silver


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Chapter 3 - Metals and Non-Metals Formative Assessment Manual for Teachers

2. Thesolutionofashobtainedafterburningmagnesiumribboninairwillturn.

a. Redlitmustobluebecauseitisacidicinnature.

b. Bluelitmustoredbecauseitisbasicinnature.

c. bluelitmustoredbecauseifisacidicinnature.

d. Redlitmustobluebecauseitisbasicinnature.

3. ___x____istheproductformedwhensulphurreactswithoxygen,itdissolvesinwater

toproduce___y___Choosecorrecloplionforxandy.

X Y

a SO2 Acid

b SO3 Neutral

c SO2 Base

d SO3 Acid

4. Sodiummetalisstoredin___x___ because itreactsvigoursly toproduce ___y___

Choosethecorrectoptionforxandy.

X Y

a Water Acidicoxide

b Alcohol Neutraloxide

c Kerosene Basicoxide

d Airtightcontainer Acidiccarbonate

5. Metal___ x___reactsvigorouslywithwatertoproducegas__y__whichburnswiththe

popsoundChoosethecorrectoptionforxandy.

X Y

a Sodium Oxygen

b Magnesium Oxygen

c Sodium Hydrogen

d Sodium Sodiumoxide


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Formative Assessment Manual for Teachers Metals and Non-Metals - Chapter 3

6. Whichofthefollowingcanbebeatenintothinsheets?

a. Zinc b. Phosphorus c. Sulphur d. Oxygen

7. Readthe followingstatementscarefully andselect thecorrectstatementsaboutthe

physicalandchemicalpropertiesofmetals-

I. Allmetalsareductile

II. Generallymetalsareductile

III. Metals which are more reactive than hydrogen react with acids to release

hydrogengas.

IV. Allmetalsreactwithacidstoreleasehydrogengas.

Thecorrectstatementoftheaboveare-

a) 1andIV b) IandIII,

c) II and III d) II and IV

8. Aluminiumfoilisusedforwrappingfoodbecause-

a. Itisductile b. Itismalleable

c. Itisagoodconductorofheat d. Itissonorous

9. Whathappenswhendilutesulphuricacidispouredonacopperplate?

a. Noreactiontakesplace b. Zincsulphateformed

c. Copperchlorideformed d. Coppersulphateformed.

10. Whichmaterialishardinnature?

a. Iron b. Graphite c. Oxygen d. sodium

11. Whichoneofthefollowingmetalisusedinthermometers?

a. Copper

b. Mercury

c. Aluminium

d. Iron

12. Correctthestatementbysubstitutingthexandywithcorrectoption.

XcantbedrawnintowiresbecauseitisnotYinnature.

X Y

a Coal Ductile

b Copper Malleable

c Aluminium Ductile

d Coal Malleable


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Chapter 3 - Metals and Non-Metals Formative Assessment Manual for Teachers

13. Zincreplacescopperfrom_X__solutionbecauseitis__Y___thancopper.Substitute

XandYwithcorrectoption.

X Y

a Zincsulphate Less reactive

b Coppersulphate more reactive

c sulphuricacid more reactive

d Coppersulphate Less reactive

14. Mostmetallicoxidesare-

a. Acidicisnature b. Neutralinnature

c. Basicinnature d. Amphotericinnature

15. ___X___isusedfordecoratingsweetsbecauseitis_Y___innature?SubstituteXandY with correct choice.

X Y

a Silverfoil Ductile

b Copperfoil Malleable

c Aluminiumfoil Ductile

d Silverfoil Malleable


Some students may nd it difcult to remember difference between ductility and

malleabilitySpendingtimeonQ.13and15willhelpremovethisdifculty.Moreover

somemnemonicmaybegiventothestudentseg.Drawnintowires-Ductility.

Somestudentsmaynditdifculttocomprehendthedifferencebetweenthesentences-

allmetalsandgenerallymostmetalshavethepropertyteachershouldhelp

theminunderstandingthedifference.

Thisworksheetshouldbeabletohelpdiagnoseanydifcultiesintheunderstandingof

theconceptsofphysicalandchemicalpropertiesofmetalsandnon-metals.


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Formative Assessment Manual for Teachers Carbon and its Compounds - Chapter 4

Carbon and its Compounds Chapter 4

Assessment technique:Contentbasedworksheet

Objectives:Toenablestudentsto-:

Learnthatethylalcoholisamajorcomponentofwine.

Learnthatvinegaris5-8%solutionofethanoicacid.

UnderstandthatethanolisoxidizedtoethanoicacidonheatingwithAlkalineKMnO4

oracidiedPotassiumdichromate.

Tocorrelatethegivenfactsaboutanorganiccompoundtosolveaproblemidentication

ofunknowncompound

Task: Individual

Proc:edure: The following worksheet may be given to the students after a teaching-learning

episodeonchemicalandphysicalpropertiesofethanolandvinegar.

Teachersmaygivethefollowinginformationtothestudentsasarecallbeforegivingthemthe

worksheet-

CH3CH2OHisamajorcomponentofwine.

AlcoholsonoxidationwithAlkalineKMnO4oracidiedPotassiumdichromateare

convertedtocarboxylicacids.

Example:CH3CH2OH CH3COOH

Vinegaris5-8%solutionofethanoicacid,itiswidelyusedasapreservativeinpickles.

Stupent Worksheet Time = 10 min

Studythegivenproblemcarefullyandanswerthefollowingquestions:

Problem-

AnorganiccompoundA(C 2H4O2)isaconstituentofwine.Thiscompound,onheatingwithalkaline

potassiumpermanganategetsoxidisedto,give,anothercompoundBwhichturnsbluelitmusred.

Q1. IdentifycompoundA.Writedownitschemicalnameandchemicalformula.

Chemicalname___________________________________________________

Chemicalformula___________________________________________________


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Chapter 4 - Carbon and its Compounds Formative Assessment Manual for Teachers

Q2. IdentifycompoundB.Writedownitschemicalnameanditschemicalformula.

Chemicalname___________________________________________________

Chemicalformula___________________________________________________

Q3. IdentifythefunctionalgroupsinthecompoundsAandB.

Q4. Write the chemical equation for. the reaction of A with alkaline KMnO4 to

produce B.

Q5. NamethetypeofreactionthattakesplaceforformationofBfromA.

Q6. WhatisthenatureofcompoundB?

Q7. Whatis5-8%solutionofBinwatercalled?


Some students may not be able to identify the compounds in the given problem.

Helpthem recall the propertiesofthe organiccompounds inthe 10thstd syllabus.

Encouragethestudentstomakeatableofpropertiesofalltheorganiccompoundsin

theircourse.

Some students may nd it difcult to write the chemical formula or identify the

functionalgroupsofthecompoundstheymaybehelpedbygivingsomeextrataskof

solvingproblems,writingtheformulaandidenticationofthefunctionalgroup.

Teachermaytakeupaquizintheclasswhereonegroupposesthequestionandother

answers.


Assessment technique:Demonstrationbasedworksheet

Objectives:Toenablestudentsto

Understandthatalcoholsandcarboxylicacidreactinpresenceofanacidcatalystto

formestersandthereactionisknownasethericationreaction.

Learnthatestersaresweetsmellingcompoundsandareusedinmakingperfumesand

avouringagents.


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Enhancetheirobservationskill.

Correlatetheoccurrenceofachemicalreactiontotheevolutionofsweetodour.

Task: Individual

Procedure:

Teachersmayperformactivityno.4.8onpage73,ofclassXNCERTSciencetextbookandmay

explainthat

Alcoholsandcarboxylicacidreactinpresenceofacidcatalysttoformestersandthe

reactionisknownasetherication.

Thechemicalreactioninvolvedintheprocessis-

CH3COOH+CH3CH2OH CH3COOC2H5

Themixtureistobeheatedinawaterbathasalcoholisinammable.

Estersaresweetsmellingcompoundsandareusedinmakingperfumesandavouring

agents.

Assessment criteria

Theteachermaymarktheanswerstothequestionsgivenintheworksheetbykeepingaweightage

of2markseachforQ.l&Q.2and1markeachforQ3toQ8

Student Worksheet Time: 10 min

Onthebasisoftheactivityperformed,answerthefollowingquestions-

Ql. Namethetworeactantstaken.

(a) __________________________________

(b) __________________________________

Q2. Identifythefunctionalgrouppresentinthetworeactants.

(a) __________________________________

(b) __________________________________

Q3. Whyisthereactionmixtureheatedonawaterbath?

Q4. Mentiononeidenticationcharacteristicoftheproductformed.


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Q5. Whatisthegeneralnameofthefunctionalgroupoftheproductformed?

Q6. Giveoneuseofthegroupofcompoundstowhichtheproductformedbelongs.

Q7. Whatisthenamegiventothistypeofreactions.

Q8. Writeachemicalequationforthereactionthathastakenplace.


Somestudentsmaynditdifculttounderstandtheformationofanesterandlinkages

intheestergroupwhencarboxylicacidandalcoholreactwitheachother.Theteacher

mayexplainthisbydepictingtheremovalofwaterfromthereactantsontheboardand

makingthestudentsrecallthatconcentratedsulphuricacidisadehydratingagent,i.e

itremoveswater.Theteachermayevenshowcharringofapaperwhenconc.sulphuric

aciddropsfallonit.

Asanextensiontotheaboveactivitytheteachermayhelpthestudentsappreciatethe

reversereactionofesterication,i.e.saponication.

Somestudentsmaynditdifculttogivereasonforheatingthereactionmixtureona

waterbath,helptheminunderstandingthisby-

1. makingthemcomparetheboilingpointsofwater,alcoholandaceticacid 2. drawingtheirattentiontowardsthefactthattheseorganiccompoundsarehighly

inammableandundergocombustiontoproduceCO2 and water


Assessment Technique:Databasedworksheet

Objectives:Toenablethestudentsto:

learnthatagroupofcompoundswithsamefunctionalgrouparecalledHomologues

discoverthat in ahomologous series thedifference in theformulaof two adjacent

compoundsisof-CH2anddifferenceinmolecularmassis-14u

appreciatethatchemicalpropertiesofmembersofaHomologousseriesaresimilar,.

formulatethegeneralformulaforahomologousseries.

PredictthenextmembersofaHomologousseries.


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Task: Individual

Procedure:

Teachermaygivethisworksheettothestudentsafter,theyhavelearnttoderiveageneralformula

forcompoundswithsamefunctionalgroups.ThefollowingbriefideaboutaHomologousseries

maybegiventothestudents.

AseriesofcompoundswithsamefunctionalgroupiscalledaHomologousseries.

EachHomologousseriescanbegivenaGeneralformulainwhichnumberofcarbon

atomisdenotedbynandthennumberofhydrogenisrelatedton.Ifanyotherhetro

elementlikeO(oxygen)ispresentinthecompound,itsnumberisalsowrittenasa

subscript.e.g.generalformulaofaekanseriesisCnH2n+2

IfoneknowsthegeneralformulaofaHomologousseries,themolecularformulaof

memberscanbewritten.Afterthecompletionoftheworksheetteachermayaddother

signicantinformationrelatedtotheconcept.

Assessment Pararneters

Question1: carries3marks

Question2: 6carries1markeach

Question7: carries2marks.

Student Worksheet Time: 15 minutes

Instructions:

Fewpairof.organiccompoundsaregivenbelow:

A. CH3OH&C2H5OH

B. C2H5OH&C3H7OH

C. C3H7OH&C4H9OH

Atomicmass:C=12u,H=1u,O=16u

Answerthefollowingquestionsonthebasisofabovedata.

Q1. Calculatethedifferenceinformulaandmolecularmassesinthepairsgivenabovea,b,and c.

Forpair(a)Differenceinformula:________;Differenceinmolecularmass:________



Q2. Whatiscommonintheaboveresult?


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Q3. NamethefunctionalGroup/GroupspresentintheHydrocarbonslistedabove.

Q4. Arrangetheabovehydrocarbonsinorderofincreasingnumberofcarbonatoms.

Q5. Whatissuchtypeofseriescalled?

Q6. WritedownageneralformulafortheseriesformedinQuestionNo.4indicatingthe

numberofC,HandOatom.

Q7. WiththehelpoftheresultofQuestionNo.1writethenexttwomembersofthisseries

obtainedinQuestionNo.4.

i) _______________________________________________________________

ii) _______________________________________________________________


Somestudentsmaynditdifculttogeneralizethattwoadjacentmembersofseries

ofsametypeofcompoundshavedifferenceof-CH2groupinformulaand14uin

molecularmass.Teachermayhelpthemrealisethisbygivingmoreexamples.

Somestudentsmaynditdifculttomakethegeneralformula,teachermayhelpthem

bygivingthemexamplesofserieswithotherfunctionalgroups(eg.alkenes,alkenes

etc.)

Somestudentsnditdifculttoextendtheseriesbyaddingmoremembers.Teacher

mayexplain,theconceptagaintothem.

FurtherteachermayaddthatchemicalpropertiesofthemembersofaHomologous

seriesaresameastheyallhavesamefunctionalgroupandchemicalpropertiesofa

compoundmainlydependsonthefunctionalgrouppresentinit.Dataaboutphysicalpropertiesofmembersofahomologousseriesmaybesharedwiththestudentstomake

themappreciatetheconstantgradationinthephysicalpropertiesofthehomologues.

Carbon and its Compounds: Chapter 4

Assessment Technique:Project

Objectives:Toenablethestudentsto-

Gainexpertiseintheskillofnaminghydrocarbons Writethestructuralformulaofhydrocarbons

Task: Individual

Procedure:

Theteachermaygivethistasktothestudentsafterexplainingtheconceptofnomenclatureof

hydrocarbons.


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Namingofacarboncompoundcanbedoneusingthefollowingsteps.Identifythelongestchain

inthecompoundcarryingfunctionalgroupandcountthenumberofcarbonatomsinthat.The

numberofcarbonatomsinthelongestchainformtherootword.

Nunber of carbons Word Root

1 meth

2 eth

3 prop

4 but

5 pent

6 hex

7 hept

8 oct

9 non

10 dec

Prexesandsufxesmaybeaddedtotherootwordaccordingtotheirpresenceinthecompound

asfollows(thefollowingrulessufcetheclassXsyllabusofCBSEandareinaccordancewith

NCERTclassXsciencebook)-

Prex+Rootword+primarysufx+secondarysufx

Primarysufxes

Identication group Class of compound Sufx

Singlebonds Alkane ane

Doublebond Alkene ene

Triplebond Alkyne yne

Prexes

Structure offunctional qroup

Class ofcompound

Prex

CI,Br halides Chloro,

bromo


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SecondarySufxes

Structure of

functional qroup

Class of

compound

Sufx

-OH alcohols -ol

-CHO aldehydes -al

-CO

ketones -one

-COOH Carboxylic

acids

-oicacid

Student Worksheet Time: 5-6 Days

Aim of the Project:

Tostudythetechniqueofnamingdifferenthydrocarbonsandnameminimum30hydrocarbonand

alsowritetheirstructuralformula.

Project Report:

Thestudentsmaybeaskedtoprepareawrittenreportoftheprojectundertakenusingtheformat

givenbelow:

AimoftheProject

Introduction

Theory

Procedure

Result

Assessment parameters:

AreaofAssessment ValuePoints

Presentation 2

Content 2

Result 2

Creativity 2

Viva 2

Total 10


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A few students may nd it difcult to write the correct name or structure of the

simplehydrocarbons,theymaybe-encouragedtonamethesimplecompoundsrstby

followingtheruies.

Some studentsmayandit difcultto differentiate betweenbaldheads, ketenesand

alcohols.whenwrittenincondensedform,theymaybehelpedbywritingtheopenand

condensedstructuresofthesamecompound.

Some studentsmayforget to count the carbon of carboxyl group in the base(root)

chain.Teachermayreiteratethatallthecarbonsthatarelinkedtoeachotherinachain

withoutanyhetroatom(O,Netc.)inbetweenaretobecountedinthechain.


Assessment Technique:DiagramBasedWorksheet

Objectives:

Toenablethestudentsto-

appreciatethatsomeelementsformcompoundsbysharingofelectronstoform,covalent

bondsUnderstandthatcarbonwithfourvalenceelectrons,formsonlycovalentbonds.

Correlate the bonds formed as single, double or triple to the number of pairs of

electronssharedbetweentheatoms,learnwritingelectronicdotstructureforformation

ofcovalent compoundscalculate and identifythe number andtypesof bonds ina

compoundformedbysharingofelectrons.

Task: Individual Procedure

Teachersmaygivethisworksheettothestudentsafterteaching-learningexperienceofbondingin

carbon.

Carbonhas4electronsinoutermostshellsoitcanneitherlooseelectronsnoraccept

electronstoattainanoblegascongurationasboththeprocessesinvolvehighenergy.

Soitformsbondbysharingitsvalenceelectronswithatomsofotherelementstogain

anorateofelectrons.Thesharedelectronsbelongtotheoutermostshellsofboththe

atomsandleadtobothatomsattainingthenobleasconguration.

Thebondformedbysharingelectronsiscalledcovalentbond,Notonlycarbon,butmanyotherelementsformmoleculesbysharingelectrons.

A single covalent bondrepresented byaline betweenthetwo atoms, is formedby

sharingonepairofelectrons.

Adoublebond representedbytwolinesbetweenthetwoatoms,isformedbysharing

twopairofelectrons.


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ATriplebondrepresentedbythreelinesbetweenthetwoatoms,isformedbysharing

3pairsofelectronsbetweentwoatoms.

Assessment Parameters:

Question1-8 carriesonemarkeach.

Question9 carry2marks.


INSTRUCTIONS:

Lookatthefollowingdiagramshowingelectronicdotstructurecarefullyandanswertheirquestions

thatfollow:

Figure4.3,4.4,4.5page44ofclassX,NCERT,ScienceTextBook.

Q1. NamethemoleculewhoseelectronicdotstructureisdepictedindiagramIandIII

Q2. Identifythetypeofbondbeingformedinthemoleculesshownabove.

Q3. Howmanypairsofelectronsarebeingsharedbetweenthetwoatomsofoxygen?

Q4. HowmanybondsareformedbetweentwoatomsofOxygen?

Q5. WritedownthestructuralformulaofthecompoundbeingshownindiagramIII.

Q6. WritetheelectronicdotstructureofMethane.

Q7. Writetheelectronicdotstructureofethene

Q8. Writetheelectronicdotstructureofpropane

Q9. Givethenumberofdifferenttypeofbondspresentinonemoleculeofpropane.


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Somestudentsmaynotknowthemolecularformulaofmethane,ethaneandpropane,teachermaygivethemtheformulabeforeaskingtowritetheelectrondotstructuresofthesecompounds.

Some students mayand it difcult to recollectthe number of valenceelectrons in

carbon and hydrogen atom and their placement around the central atom for bondformation.Theymaybehelpedbyaskingthemtowritetheelectroniccongurationsoftheelementstondthenumberofvalenceelectronsandvaliancysomestudentsmaymiss,abondwhilecountingdifferenttypeofbonds.

They maybeasked to be cautious whilecountingthe number of bondsincaseof

doubleandtriplebondedcompounds.

Carbon and its Compounds Chapterh 4

Assessment Technique:ContentbasedAssessment.Objective:Toenablethestudentsto

Recall chemical properties of hydrocarbons, alcohols and carboxylic acids. Write

chemicalequationsfortheorganicreactionswithmainproductsformedduringthe

reaction.

Drawcorrelationsbetweenthetypeoffunctionalgroupandthechemicalpropertiesof

organiccompounds.

Recognise variousreagentslike-a reducing or an oxidising agentusedin organic

reactions.

Task: Individual

Procedure:

Thefollowingformativeassessmentsheetmaybegiventothestudentstoassesstheirunderstanding

ofthechemicalpropertiesshownbyhydrocarbons,alcoholsandcarboxylicacids.

Arevisionofthefollowingconceptsmaybedonebeforetheassessment.

Hydrocarbonsburn,inoxygentogivecarbondioxide,waterandheat.

AlcoholwhenheatedwithAlkalineKMnO4oracidiedpotassiumdichromate,are

convertedtocarboxylicacid.

UnsaturatedhydrocarbonsaddhydrogeninthepresenceofcatalystssuchasPalladium

ornickeltogivesaturatedhydrocarbons.

Inthepresenceofsunlight,saturatedhydrocarbonsundergosubstitutionreactingwith

chlorine.

Alcoholreactwithsodiummetaltoformsodiumalkoxideandhydrogengas.


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Onheatingethanolwithexcesscone.H2SO4at443Kethaneandwaterisformed.

Whencarboxylicacidandalcoholreactingpresenceofacid,sweetsmellingesteris

formedandesterreactinpresenceofanacidorabasetogivebackthealcoholand

carboxylicacid.

CarboxylicacidreactswithabaselikeNaOHtogivesodiumsaltofcarboxylicacidand water.

Carboxylicacidreactswithcarbonatesandhydrogencarbonatestogivesalts,water

andcarbondioxide.

Assessment Parameters:

Onemarkforeverycorrectchemicalequation.Thereactionsshouldclearlyshowthecatalystused

andthemajorproductsformed.Balancingoforganicreactionsisnotmust.Reactionsgiven

inNCERT.chapterIV,classXtextbookmaybeusedascriteriaofmarking.


Writebalancedchemicalequationforthefollowingchemicalreaction:

A. CombustionofMethane.

B. Reactionofethanolwithhotalkalinepotassiumpermanganate.

C. ReactionofpropenewithHydrogeninpresenceofpalladiumornickel

D. ReactionofMethanewithchlorineinpresenceofsunlight.

F. ReactionofethanolwithSodiumMetal

G. Whenethanolisreactedwithhotconc.SulphuricAcid.

H. Reactionofethanoicacidwithethanolinpresenceconc.H2SO4.

I. Reactionofethylethanoate(CH3COOC2H5)withSodiumhydroxide.


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J. Reactionofethanoicacidwithsodiumhydroxide.

K. ReactionofethanoicacidwithSodiumbicarbonate


Some.studentsmaynditdifculttowritethecorrectformulaofanorganiccompound.

Teachermayencouragethestudentstowritethegeneralformulaeandthefunctional

groupsoforganiccompoundsintheirsyllabusonachartandrevisitthenamingof

organiccompounds.

Some students maynd it difcult to recall theproductsof thechemicalreaction

orbalancetheequation.Theteachermayaskthemtotabulateallthereactionsofa

particularfunctionalgrouptogetheranddrawcorrelationsinthereactions.Correlations

serveasamemorytool.


Assessment technique:ContentBased(orWritingchemicalformula)

Objectives:Toenablethestudentsto

Writedownthemolecularformulaofhydrocarbons.

Recognisethefunctionalgroupthroughthenameofthehydrocarbon.

Appreciatethatifmolecularformulaandfunctionalgrouppresentinthecompoundis

known,structureofthecompoundcanbewritten.

Task: Individual

Procedure:

This worksheet may be given to the students after teaching them the nomenclature of the

hydrocarbonsandskillofdrawingthestructureofhydrocarbon.

Assessment parameter:Everycorrectanswercarries1mark.

Student Worksheet Time: 10 min.

Instructions:

Writethemolecularformulaanddrawthestructureforthefollowingcompounds.


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Compound Molecular formula Structure

Ethanoicacid

Bromopentane

Butanone

Hexanal

Heptyne


Somestudentsmaynotbeabletorecallthemolecularformulaofthecompoundso

maydrawthestructurewrong,Teachermayneedtorepeattherevisionexercise.

AfewstudentsmaynotcountCarbonofCarboxylgroupinthebasechainandmay

writeethanoicacidasC2H5COOH.Teachermayneedtorevisetheconcept-andexplain

thenthatallthecarbonsthatarelinkedtoeachotherinachainwithoutanyheteroatominbetweenaretobecountedinrootchain.

Somestudentsmayassumethehexanaltobeanalcohol.

Somestudentsmaynotconsiderthebalanceofcarbonwhilewritingthestructureof

compounde.g.Heptyneandcarbonmaybeforming5bonds.Teacherneedtoexplain

tothemthesignicanceofnumberofbondsfermedbyacarbonatom.


Assessment technique:DatabasedWorksheet


UnderstandtheHomologousseriesanditscharacteristics.

WritethegeneralformulaofHomologousseries.

Applythegeneral formulaofa homologous series to identifyanycompound in he

series.

Task: Individual

Procedure:

Teacher maygive this worksheet to the students after teaching - learning the concept ofThe

homologousseries.

Teachermaygivethefollowinginformationtothestudentsasarecall:-

AserieswiththehydrocarbonshavingsamefunctionalgroupiscalledHomologous

series.


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Differenceintheformulaandmolecularmassoftwoconsecutivecompoundsmembers

ofsame

Homologousseriesis-CH2and-14urespectively.

A homologous series can be identied with a general formula which helps in

determiningtheothermembersoftheseries.

Assessment parameters:Asindicatedintheworksheet.


Instructions:

Arunwrotefewseriesofhydrocarbonandleftblanksinbetween.Lookatthechemicalformulain

theseriesofhydrocarbonscarefullyandanswerthequestionsthatfollow:

I II III IV V

CH4 C2H4 C2H2 CH3OH D

C2H6 C3H6 B C2H5OH CH3COOH

C3H8 A C4H6 C3H7OH C2H5COOH

C4H10 C5H10 C5H8 C C3H7COOH

Ql. WhatisthedifferenceintheformulaandmolecularmassbetweenC2H6&C3H8;C3H8

andC4H10?

Q2. WhataresuchseriesofHydrocarbonscalled?

Q3. SubstitutetheblanksA,B,C,Dwithcorrectchemicalformulaofthecompound. A. _________________________ B. _________________________

C. _________________________ D. _________________________

Q4. NamethefunctionalgrouppresentintheseriesIV&V.

Q5. Whichistherstmemberofthealkaneseries?

Q6. Whatisthegeneralformulaofthehomologousseriesofalkyneandalcohol.

Q7. Name the chemical formula of 6th member of alkyne series and 15th member of

alcohol series.


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Somestudentsmaynotbeabletomakeandusethegeneralformulaofhomologous

seriesofalkyneandalcohol.Theymaybegivenmorepracticeusingdifferentexamples

fromsameanddifferenthomologousseries.

SomestudentsmaynottoabletoidentifythecompoundandfunctionalgrouppresentinthatHelpthemtorecallthesame.


Assessment technique:FactsbasedWorksheet


Learnthebasicfactsaboutcarbonatomlikeelectronicconguration,valencyandits

combustion.

understandtheversatilenatureofcarbonatom.

Appreciatethatcarbonformscompoundsbysharingelectrons.

Learnthatalkanesaresaturatedbutalkenesandalkynesareunsaturated

hydrocarbonswherepairofcarbonsarebondedwithdoubleandtriplecovalentbond

respectively.

Task: Individual

Procedure:

Teachermaygivethisworksheettothestudentsafterdiscussingaboutthenatureofcarbonatom

anditsbondingability

Teachermaygivethefollowinginformationtothestudentsasarecall:-

CompoundsofcarbonandhydrogenarecalledHydrocarbons.

Carbonformscovalentbondsbysharingtheelectrons.

Alkanesaresaturatedhydrocarbonswithapairofcarbonatomsbondedtogetherwith

doublebond.

Alkynesareunsaturatedhydrocarbonswithapairofcarbonatomsondedtogetherwithtriplebond.

HydrocarbonsoncombustionproduceCO2,H2Oheatandenergy.

Functionalgroupareatomsorgroupofatomspresentinhydrocarbonwhichdetermines

itschemicalproperties.

Assessment parameters:Asindicatedintheworksheet.(Q1-Q81mark)


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Student Worksheet Time : 10 min

Kunalgotafactsheetaboutcarbonatomwhichhasstormedhisbrainwithmanyquestions.

Atomicnumberofcarbonis6.

Itistetravalentinnaturethatiswhyonecarbonatomcombineswith4Hydrogenatomtoformmethane.

Itcanneithergiveelectronortakeelectrontoformacompound.

It hasa versetilenature andformmany hydrocarbon likealkanesalkenes,alkynes,

alcohol,carboxylicacid.

The chemical properties of hydrocarbon , are determined by the functional group

presentinit.

Fewofthequestionsarelistedbelowcanyouhelphimwiththeanswers.Tryit

Q1. Whatistheelectroniccongurationofcarbon?

Q2. Carbonistetravalentinnature.Whatdoesitmean?

Q3. Whatisthevalanceofcarboninethane?

Q4. Carbonneithergiveselectronortakeselectronthenhowdoesitcompleteitsoctetand

whatisthetypeofbondtoformed.

Q5. Whatisahydrocarbon?


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Q6. Whatisthedifferencebetweenalkanesandalkenes?

Q7. When carbon is burnt carbon dioxide is formed. Name the products formed when

hydrocarbonsareburnt.

Q8. Whatisafunctionalgroup?

Q9. Whydoescarbonformmanycompounds?(Givetworeasons)

1.

2.


A fewstudents maybe puzzled to ndoutthevalenceof carbon in ether.Teachermayneedtoexplain.Ascarbonthatvalenceofcarbonneverchanges(Valenceisthe

Capacitytoformbondshasfourelectroninoutermostshellitsvaluanceis4)

A few students may write that alkanes are saturated and alkenes are unsaturated

hydrocarbonoralkeneshaveonepairofcarbonatomsbondedwithdoublebond.

Afewstudentsmaynotcorrelatethatoneofthemajorcomponentofhydrocarbonis

carbonandthereforetheircombustionalsoleadstotheproductionofCO2andH2O

heatandlightTeachermayhelpthemtounderstand.


Assessment technique:FormulaBasedWorksheet(Brainstorming)

Objectives:Toenablethelearnersto

Learnthemolecularformulaofahydrocarbonandwithitsstructureandversa.


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Establish the relation between Hydrocarbons molecular formula and structure and

name

Applytheconceptofnomenclatureofhydrocarbon.

Task : Individual

Procedure:

TeachermaygivethisworksheettothestudentstoaccesstheirunderstandingofNomenclatureof

hydrocarbonsandskillofdrawingthestructureofthehydrcabon,

Assessment parameter:Eachquestioncarries2marks


Instructions:

Givenbelowarethename,molecularformulaandstructureofafewhydrocarbons.Inoneofthe

threecolumns,thereissomeerror.Identifythewrongentryandwritethecorrectanswerinthebox

givenbeside.

Hydrocarbon Formula Structure

Propanol C3H8O

H H H| | |

H C C C = O| |

H H

Chlorobutane C4H8CI

H H H H| | | |

H C C C C Cl| | | |

H H H H

Ethanoicacid C2H5COOH

H H O| | ||

H C C C OH| |

H H

Propanone C3H7O

H O H| || |

H C C C H| |

H H


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54


Heptyne C7H14

H H H H H| | | | |

H C C C C C C = C H| | | | |

H H H H H


Somestudentsmaynotbeabletoestablishtherelationofhydrocarbon-name,molecularformula,structure,theyneedtobegivenmorepractice.

Somestudentsmaynotbeabletorecallthemolecularformula.

Somemaynotincludethecarbonofcarboxylgroupinbasechain.Teachermayneedtoguidethem.

Somestudentsmaynotcheckthevalenceofthecaronatome.g.(inHeptyne)andso

maynotndanyerrorinquestion5.Theyneedtoexplainthesame.


Assessment technique:Contentbased


understandandlearnthechemicalpropertiesofHydrocarbons..

Identifythereactantsusedandproductsformedindifferentreactions.

Task: Individual

Procedure:

Teacher may give this worksheet to the students after teaching - learning the properties of

Hydrocarbons.Assessmentparameter-1markforeachcorrectanswer

Student Worksheet

Instructions:

Mr.Puriexplainedthechemicalpropertiesofhydrocarbonstostudentsandwrotethechemical

equationsforthereactions.Heaskedthestudentstonotethemintheirnotebooks.Suddenlythe

bellrang.Ashemovedout,Rishelrubbedafewcompoundsfromtheblackboard.Nowstudents

areinafuss.Canyouhelptheminplacingchemicalformulaofcorrectcompoundtocompletethe

chemicalequationforthereactions:


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Try

1. CH4+O2 _________________+H2O+heatandlight

AlkalineKMnO42. CH3CH2OH _________________ HH

NiCatalyst| |

3. _________________ RCCR

| |

RR

Sunlight4. CH4+_________ CH3Cl+HCl

5. CH3CH2OH+2Na _______________

Hot.Conc.H2SO46. CH3CH2OH _______________

Acid7. CH3CH2OH+CH3COOH _______________8. CH3CH2COOC2H5+NaOH _______________+C2H5OH9. CH3COOH+_______________ CH3COONa+H2O10. CH3COOH+NaHCO3 CH3COONa+H2O+_______________


Somestudentsmaynditdifculttoidentifytheproductorguessthereactantusedinthe chemical reaction.

Teachermayhelpthemrecallthelearningandrepheattherevisionexcerise.


Assessment technique: Matchthecolumn


learnthenomenclatureofthehydrocarbonsapplytheunderstandingoftechniqueof

namingofhydrocarbons

Identifythereactantsusedandproductsformedindifferentreactions.

Task : Individual


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Procedure:

Teacher may give this worksheet to the students after teaching - learning of

Nomenclatureofthehydrocarbons.Followingpointsmayberecalledinconcernwith

thenomenclatureofhydrocarbons.

Carboninthebasicchainwithfunctionalgroupisidentiedandnamedusingsuitableprexorsufxforthefunctionalgroupe.g. ifitisalcoholsufxusedisolandif

aldehydesufxusedisol.

Tonameacyclicalkanesufxusediscyclo.

C6H6isbenzene.

Assessment parameter:1markforeverycorrectmatch.


Instructions:

MatchthestructuresofhydrocarbonsgivenincolumnBwiththeirIUPACnamesincolumnCand

writethecorrespondings.no.numbertothecorrectnameincolumnA


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Somestudentsmaynotrecalltheprexforaparticularnumberofcarbonandmay

namethebasechainwrong.

Somestudentsmayconfusebetweentheprexalisforalcohol.

Afewstudentsmaynotdifferentiatethestructurecyclohexaneandbenzene.

Afewstudentsmaynotcountthecarbonofcarboxylgroupinthebasechain.Teacher

mayrepeattherevisionexercise.


Assessment technique:Matchthecolumn


Understandthenomenclatureofthehydrocarbons.

Identifythenameofahydrocarbon.

AppreciatethegeneralformulaofaHomologousseries.

Task: Individual

Procedure:

Teachermaygivethisworksheettothestudentstopracticethenomenclatureofthehydrocarbons

afterteachingthesame.

TypesofbondsanduseofgeneralformulaofaHomologousseriesshouldberecalledpriortothat.

GeneralformulaofAlkanesseriesisCnH2n+2.lnitallthebondsaresingle.

GeneralformulaofAlkenesisCnH2n.Itcontainsonedoublebond.

GeneralformulaofAlkynesseriesisCnH2n2.Itcontainsonetriplebond.

Assessment parameter:

1 mark for every correct match andone mark for completing andverifying the magicsquare

correctly.


Instructions:

Putthenumberofthehintfromthelistintothesquarewithappropriatematch.Checkyouranswer

byaddingthenumberstoseeifallthesumoftherowsbothacrossanddownadduptothesame

number,themagicnumber.


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CH3COOH C5H10 CH3COOH Magicnumber

CH3CH2CI HCHO C15H32 Magicnumber

CH3COCH3 C6H10 C2H5OH Magicnumber

Magicnumber Magicnumber Magicnumber

HINT LIST:

1. Ethanol

2. Chloroethane

3. Analkene

4. Methanal

5. Itsdil.FormisusedasVinegar.

6. Ketonewith3carbonatom.

7. Analkyne

8. Containsatriplebond.

9. Analkane.


Afewstudentsmaynotassociateallthesquareswiththecorrecthint,confusionmay

be between methanol and methanal.

Studentscancheckthemselvesbyaddingthenumberintherowsandthinkoverthe

answeragainorteachermayhelpthemtorecall.


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Formative Assessment Manual for Teachers Period Classication of Elements - Chapter 5

Period Classication of Elements Chapter 5

Assesment Technique: DataBasedWorksheet


LearnthesalientfeaturesoftheModernPeriodictable.

Understandthetrendsofdifferentpropertiesontheperiodictable.

Task: Individual

Procedure:

Thisworksheetmaybegiventothestudentsafterrecallingthesalientfeaturesofthe

periodictableusingachartdisplayingModernPeriodicTable.

Thevalenceelectronschangeacrossaperiodbutremainssameinthegroupsandso

thevalency.

Atomicsizedecreasesacrossaperiodbutincreasesdownthegroup.

Metalliccharacterdecreasesacrossaperiodbutincreasesdownthegroup.

Nonmetalliccharacterincreasesacrossaperiodbutdecreasesdownthegroup.

Assessment Parameter

markforeachcorrectanswer

Student Worksheet

ReadthefollowinglineswrittenabouttheModernPeriodicTableandllintheblanks

IamtheModernPeriodicTable,whereelementsarearrangedonthebasisof______________.

I have ______________ Horizontal rows called______________ and ____________

verticalcolumnsarecalled______________.Myrstperiodisveryshortwith__________

elementsand 2 and3 Period contain ____________elements, 4 and5 has____________

elements. 6 period has____________elements but 7 period is____________. With spacefor more elements.17 group isof____________ 18 isof____________.Atomic size of

myelements____________acrosstheperiodbut____________downthegroupsameas

the metallic character but the non metallic character is____________to that Number of

valenceelectrons____________acrosstheperiodsovariesthevalencybutvalencyofthe

elementsis____________inagroup.AllthepropertiesofelementsarethePeriodicfuction

of____________.


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Chapter 5 - Period Classication of Elements Formative Assessment Manual for Teachers


Afewstudentsmaynotrecollectthesalientfeaturesofthemodernperiodictable.

thetablecanbedisplayedforthehelp.

Afewstudentsmaynotrecallthetrendindifferentproperties.

Teachermayexplainthesameagain.

TeachermaysuggestthestudentstolearnthePoem.

Period Classication of Elements Class 5

Assesiytent Technique:Diagram/(PeriodicTable)BasedWorksheet


Appreciatetheperiodictrendsinpropertiesofelements.

Learnsalientfeaturesofnewperiodictable.

Studyandanalysethegiventablefortheplacementandpropertiesofelementsinthe

ModernPeriodicTable.

Task: Individual

Procedure:

The teacher, may give the following worksheet after the teaching-learning about the modernperiodic table. The following information may be recalled with the students before they start

workingontheworksheet:

Elementsof1stgrouparecalledalkalimetals,

2ndgroupelementsarecalledalkalineEarthmetals,

Elements of group 17 are called Halogens and that of group 18, are called

noblegases.

Atomicnumberofelementsincreasesfromlefttorightintheperiodandtoptobottom

inthegroupinperiodictable.,

Valency(thecombiningcapacity)ofanelementcanbe.determinedby-

1. Thenumberof,valenceelectronsifthenumberisequaltoorlessthan4.

2. (8-Valenceelectrons)ifthenumberofvalenceelectronsismorethan4.

3. Thegroupnumberforelementsofgroup1and2.

cbse class x (science) page 31 60

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