Metals and Non-metals Chapter 3 · 2016-10-31 · metals, their compounds and gases evolved during...

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

c. Whatisthebrownflakysubstance?

d. Whatarethecommonvalenciesshownbymetal‘M’?

Suggested Remediation:

● Somestudentsmayfinditdifficult toremembervariousreactionsandpropertiesofmetals, their compounds and gases evolved during reactions of the carbonates andsulphideoreswithdiluteacids.Theymaybeencouragedtotabulatevariousreactionsofmetalsingeneralformandbefamiliarwithallthereactions.

● Revisitingchapter1‘ChemicalReactionsandEquations’mayberequiredforstudentswhofinditdifficulttowritebalancedchemicalreactions.

● Attentionofthestudentsmaybedrawntowardscategorisingthereactionsintovarioustypesstudiedinchapter1.

Metals and Non-metals Chapter 3

Assessment Technique:MultipleChoiceQuestionsBasedWorksheet

Objectives:Toenablestudentsto-

● Recallvariousphysicalandchemicalpropertiesofmetalsandnon-metals.

● DrawcorrelationbetweentheoxideofanelementandpHofitsaqueoussolution.

● Recallreactivityseriesofmetalstopredicttheproductsofareaction.

● Applytheconceptualknowledgetodailyusesoftheelements.

Task: Individual

Procedure:

ThestudentsmaybegiventhefollowingMCQbasedworksheetaftertheteaching-learningofthecompleteunit‘MetalsandNon-metals’tostrengthentheconcepts.

Assessment Parameters:Eachofthefollowingquestionsmaybeassessedgivingequalweightageof1marktoeachcorrectanswer.

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,itdissolvesinwatertoproduce___y___Choosecorrecloplionforxandy.

X Y

a SO2 Acid

b SO3 Neutral

c SO2 Base

d SO3 Acid

4. Sodiummetal isstored in___x___because it reactsvigoursly toproduce___y___ Choosethecorrectoptionforxandy.

X Y

a Water Acidicoxide

b Alcohol Neutraloxide

c Kerosene Basicoxide

d Airtightcontainer Acidiccarbonate

5. Metal___x___reactsvigorouslywithwatertoproducegas__y__whichburnswiththe“pop”soundChoosethecorrectoptionforxandy.

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. Read the followingstatementscarefullyandselect thecorrect statementsabout thephysicalandchemicalpropertiesofmetals-

I. Allmetalsareductile

II. Generallymetalsareductile

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

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.

Xcan’tbedrawnintowiresbecauseitisnotYinnature.

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.SubstituteXandYwithcorrectoption.

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 find it difficult to remember difference between ductility andmalleabilitySpendingtimeonQ.13and15willhelpremovethisdifficulty.Moreoversomemnemonicmaybegiventothestudentseg.Drawnintowires-Ductility.

● Somestudentsmayfinditdifficulttocomprehendthedifferencebetweenthesentences-’allmetals—’and‘generallymostmetalshave theproperty—teachershouldhelptheminunderstandingthedifference.

● Thisworksheetshouldbeabletohelpdiagnoseanydifficultiesintheunderstandingoftheconceptsofphysicalandchemicalpropertiesofmetalsandnon-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 oracidifiedPotassiumdichromate.

● Tocorrelatethegivenfactsaboutanorganiccompoundtosolveaproblemidentificationofunknowncompound

Task: Individual

Proc:edure: The followingworksheet may be given to the students after a teaching-learningepisodeonchemicalandphysicalpropertiesofethanolandvinegar.

Teachersmaygivethefollowinginformationtothestudentsasarecallbeforegivingthemtheworksheet-

● CH3CH2OHisamajorcomponentofwine.

● AlcoholsonoxidationwithAlkalineKMnO4oracidifiedPotassiumdichromateareconvertedtocarboxylicacids.

● Example:CH3CH2OH CH3COOH

● Vinegaris5-8%solutionofethanoicacid,itiswidelyusedasapreservativeinpickles.

Stupent Worksheet Time = 10 min

Studythegivenproblemcarefullyandanswerthefollowingquestions:

Problem-

AnorganiccompoundA(C2H4O2)isaconstituentofwine.Thiscompound,onheatingwithalkalinepotassiumpermanganategetsoxidisedto,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.Help them recall thepropertiesof theorganic compounds in the10th std syllabus.Encouragethestudentstomakeatableofpropertiesofalltheorganiccompoundsintheircourse.

● Some students may find it difficult to write the chemical formula or identify thefunctionalgroupsofthecompoundstheymaybehelpedbygivingsomeextrataskofsolvingproblems,writingtheformulaandidentificationofthefunctionalgroup.

● Teachermaytakeupaquizintheclasswhereonegroupposesthequestionandotheranswers.


Assessment technique:Demonstrationbasedworksheet

Objectives:Toenablestudentsto

● Understandthatalcoholsandcarboxylicacidreactinpresenceofanacidcatalysttoformestersandthereactionisknownasetherificationreaction.

● Learnthatestersaresweetsmellingcompoundsandareusedinmakingperfumesandflavouringagents.

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● Enhancetheirobservationskill.

● Correlatetheoccurrenceofachemicalreactiontotheevolutionofsweetodour.

Task: Individual

Procedure:

Teachersmayperformactivityno.4.8onpage73,ofclassXNCERTSciencetextbookandmayexplainthat—

● Alcoholsandcarboxylicacidreactinpresenceofacidcatalysttoformestersandthereactionisknownasetherification.

● Thechemicalreactioninvolvedintheprocessis-

CH3COOH+CH3CH2OH CH3COOC2H5

● Themixtureistobeheatedinawaterbathasalcoholisinflammable.

● Estersaresweetsmellingcompoundsandareusedinmakingperfumesandflavouringagents.

Assessment criteria —

Theteachermaymarktheanswerstothequestionsgivenintheworksheetbykeepingaweightageof2markseachforQ.l&Q.2and1markeachforQ3toQ8

Student Worksheet Time: 10 min

Onthebasisoftheactivityperformed,answerthefollowingquestions-

Ql. Namethetworeactantstaken.

(a) __________________________________

(b) __________________________________

Q2. Identifythefunctionalgrouppresentinthetworeactants.

(a) __________________________________

(b) __________________________________

Q3. Whyisthereactionmixtureheatedonawaterbath?

Q4. Mentiononeidentificationcharacteristicoftheproductformed.

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Q5. Whatisthegeneralnameofthefunctionalgroupoftheproductformed?

Q6. Giveoneuseofthegroupofcompoundstowhichtheproductformedbelongs.

Q7. Whatisthenamegiventothistypeofreactions.

Q8. Writeachemicalequationforthereactionthathastakenplace.


● Somestudentsmayfinditdifficulttounderstandtheformationofanesterandlinkagesintheestergroupwhencarboxylicacidandalcoholreactwitheachother.Theteachermayexplainthisbydepictingtheremovalofwaterfromthereactantsontheboardandmakingthestudentsrecallthatconcentratedsulphuricacidisadehydratingagent,i.eitremoveswater.Theteachermayevenshowcharringofapaperwhenconc.sulphuricaciddropsfallonit.

● Asanextensiontotheaboveactivitytheteachermayhelpthestudentsappreciatethereversereactionofesterification,i.e.saponification.

● Somestudentsmayfinditdifficulttogivereasonforheatingthereactionmixtureonawaterbath,helptheminunderstandingthisby-

1. makingthemcomparetheboilingpointsofwater,alcoholandaceticacid

2. drawingtheirattentiontowardsthefactthattheseorganiccompoundsarehighlyinflammableandundergocombustiontoproduceCO2 and water


Assessment Technique:Databasedworksheet

Objectives:Toenablethestudentsto:

● learnthatagroupofcompoundswithsamefunctionalgrouparecalledHomologues

● discover that in a homologous series thedifference in the formulaof two adjacentcompoundsisof‘-CH2’anddifferenceinmolecularmassis‘-14u’

● appreciatethatchemicalpropertiesofmembersofaHomologousseriesaresimilar,.formulatethegeneralformulaforahomologousseries.

● PredictthenextmembersofaHomologousseries.

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Task: Individual

Procedure:

Teachermaygivethisworksheettothestudentsafter,theyhavelearnttoderiveageneralformulaforcompoundswithsamefunctionalgroups.ThefollowingbriefideaboutaHomologousseriesmaybegiventothestudents.

● AseriesofcompoundswithsamefunctionalgroupiscalledaHomologousseries.

● EachHomologousseriescanbegivenaGeneralformulainwhichnumberofcarbonatomisdenotedbynandthennumberofhydrogenisrelatedton.Ifanyotherhetroelementlike‘O’(oxygen)ispresentinthecompound,itsnumberisalsowrittenasasubscript.e.g.generalformulaofaekanseriesisCnH2n+2

● IfoneknowsthegeneralformulaofaHomologousseries,themolecularformulaofmemberscanbewritten.Afterthecompletionoftheworksheetteachermayaddothersignificantinformationrelatedtotheconcept.

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.4indicatingthenumberofC,HandOatom.

Q7. WiththehelpoftheresultofQuestionNo.1writethenexttwomembersofthisseriesobtainedinQuestionNo.4.

i) _______________________________________________________________

ii) _______________________________________________________________


● Somestudentsmayfinditdifficulttogeneralizethattwoadjacentmembersofseriesofsametypeofcompoundshavedifferenceof-’CH2groupinformulaand‘14u’inmolecularmass.Teachermayhelpthemrealisethisbygivingmoreexamples.

● Somestudentsmayfinditdifficulttomakethegeneralformula,teachermayhelpthembygivingthemexamplesofserieswithotherfunctionalgroups(eg.alkenes,alkenesetc.)

● Somestudentsfinditdifficulttoextendtheseriesbyaddingmoremembers.Teachermayexplain,theconceptagaintothem.

● FurtherteachermayaddthatchemicalpropertiesofthemembersofaHomologousseriesaresameastheyallhavesamefunctionalgroupandchemicalpropertiesofacompoundmainlydependsonthefunctionalgrouppresentinit.Dataaboutphysicalpropertiesofmembersofahomologousseriesmaybesharedwiththestudentstomakethemappreciatetheconstantgradationinthephysicalpropertiesofthehomologues.

Carbon and its Compounds: Chapter 4

Assessment Technique:Project

Objectives:Toenablethestudentsto-● Gainexpertiseintheskillofnaminghydrocarbons● Writethestructuralformulaofhydrocarbons

Task: Individual

Procedure:

The teachermaygive this task to thestudentsafterexplaining theconceptofnomenclatureofhydrocarbons.

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Namingofacarboncompoundcanbedoneusingthefollowingsteps.Identifythelongestchainin thecompoundcarryingfunctionalgroupandcount thenumberofcarbonatomsinthat.Thenumberofcarbonatomsinthelongestchainformtherootword.

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

Prefixesandsuffixesmaybeaddedtotherootwordaccordingtotheirpresenceinthecompoundasfollows(thefollowingrulessufficetheclassXsyllabusofCBSEandareinaccordancewithNCERTclassXsciencebook)-

Prefix+Rootword+primarysuffix+secondarysuffix

Primarysuffixes

Identification group Class of compound Suffix

Singlebonds Alkane ane

Doublebond Alkene ene

Triplebond Alkyne yne

Prefixes

Structure of functional qroup

Class of compound

Prefix

CI,Br halides –Chloro,

– bromo

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SecondarySuffixes

Structure of functional qroup

Class of compound

Suffix

-OH alcohols -ol

-CHO aldehydes -al

-CO– ketones -one

-COOH Carboxylic

acids

-oicacid

Student Worksheet Time: 5-6 Days

Aim of the Project:

Tostudythetechniqueofnamingdifferenthydrocarbonsandnameminimum30hydrocarbonandalsowritetheirstructuralformula.

Project Report:

Thestudentsmaybeaskedtoprepareawrittenreportoftheprojectundertakenusingtheformatgivenbelow:

● 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 find it difficult to write the correct name or structure of thesimplehydrocarbons,theymaybe-encouragedtonamethesimplecompoundsfirstbyfollowingtheruies.

● Some studentsmay and it difficult to differentiate betweenbaldheads, ketenes andalcohols.whenwrittenincondensedform,theymaybehelpedbywritingtheopenandcondensedstructuresofthesamecompound.

● Some studentsmay forget to count the carbon of carboxyl group in the base(root)chain.Teachermayreiteratethatallthecarbonsthatarelinkedtoeachotherinachainwithoutanyhetroatom(O,Netc.)inbetweenaretobecountedinthechain.


Assessment Technique:DiagramBasedWorksheet

Objectives:

Toenablethestudentsto-

● appreciatethatsomeelementsformcompoundsbysharingofelectronstoform,covalentbondsUnderstandthatcarbonwithfourvalenceelectrons,formsonlycovalentbonds.

● Correlate the bonds formed as single, double or triple to the number of pairs ofelectronssharedbetweentheatoms,learnwritingelectronicdotstructureforformationof covalent compounds calculate and identify the number and types of bonds in acompoundformedbysharingofelectrons.

Task: Individual Procedure

Teachersmaygivethisworksheettothestudentsafterteaching-learningexperienceofbondingincarbon.

● Carbonhas4electronsinoutermostshellsoitcanneitherlooseelectronsnoracceptelectronstoattainanoblegasconfigurationasboththeprocessesinvolvehighenergy.Soitformsbondbysharingitsvalenceelectronswithatomsofotherelementstogainanorateofelectrons.Thesharedelectronsbelongtotheoutermostshellsofboththeatomsandleadtobothatomsattainingthenobleasconfiguration.

● Thebondformedbysharingelectronsiscalledcovalentbond,Notonlycarbon,butmanyotherelementsformmoleculesbysharingelectrons.

● Asinglecovalentbond representedbya linebetween the twoatoms, is formedbysharingonepairofelectrons.

● Adoublebond representedbytwolinesbetweenthetwoatoms,isformedbysharingtwopairofelectrons.

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● ATriplebondrepresentedbythreelinesbetweenthetwoatoms,isformedbysharing3pairsofelectronsbetweentwoatoms.

Assessment Parameters:

Question1-8 carriesonemarkeach.

Question9 carry2marks.


INSTRUCTIONS:

Lookatthefollowingdiagramshowingelectronicdotstructurecarefullyandanswertheirquestionsthatfollow:

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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Suggested Remediation:● Somestudentsmaynotknowthemolecularformulaofmethane,ethaneandpropane,

teachermaygivethemtheformulabeforeaskingtowritetheelectrondotstructuresofthesecompounds.

● Some studentsmay and it difficult to recollect the number of valence electrons incarbon and hydrogen atom and their placement around the central atom for bondformation.Theymaybehelpedbyaskingthemtowritetheelectronicconfigurationsoftheelementstofindthenumberofvalenceelectronsandvaliancysomestudentsmaymiss,abondwhilecountingdifferenttypeofbonds.

● Theymaybe asked to be cautiouswhile counting the number of bonds in case ofdoubleandtriplebondedcompounds.

Carbon and its Compounds Chapterh 4

Assessment Technique:ContentbasedAssessment.

Objective:Toenablethestudentsto

● Recall chemical properties of hydrocarbons, alcohols and carboxylic acids.Writechemicalequations for theorganic reactionswithmainproducts formedduring thereaction.

● Drawcorrelationsbetweenthetypeoffunctionalgroupandthechemicalpropertiesoforganiccompounds.

● Recognise various reagents like -a reducing or an oxidising agent used in organicreactions.

Task: Individual

Procedure:

Thefollowingformativeassessmentsheetmaybegiventothestudentstoassesstheirunderstandingofthechemicalpropertiesshownbyhydrocarbons,alcoholsandcarboxylicacids.

Arevisionofthefollowingconceptsmaybedonebeforetheassessment.

● Hydrocarbonsburn,inoxygentogivecarbondioxide,waterandheat.

● AlcoholwhenheatedwithAlkalineKMnO4 or acidifiedpotassiumdichromate, areconvertedtocarboxylicacid.

● UnsaturatedhydrocarbonsaddhydrogeninthepresenceofcatalystssuchasPalladiumornickeltogivesaturatedhydrocarbons.

● Inthepresenceofsunlight,saturatedhydrocarbonsundergosubstitutionreactingwithchlorine.

● Alcoholreactwithsodiummetaltoformsodiumalkoxideandhydrogengas.

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● Onheatingethanolwithexcesscone.H2SO4at443Kethaneandwaterisformed.

● Whencarboxylicacidandalcoholreactingpresenceofacid,sweetsmellingesterisformedandesterreactinpresenceofanacidorabasetogivebackthealcoholandcarboxylicacid.

● CarboxylicacidreactswithabaselikeNaOHtogivesodiumsaltofcarboxylicacidand water.

● Carboxylicacidreactswithcarbonatesandhydrogencarbonatestogivesalts,waterandcarbondioxide.

Assessment Parameters:

Onemarkforeverycorrectchemicalequation.Thereactionsshouldclearlyshowthecatalystusedandthemajorproductsformed.Balancingoforganicreactionsisnotmust.ReactionsgiveninNCERT.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.studentsmayfinditdifficulttowritethecorrectformulaofanorganiccompound.Teachermayencouragethestudentstowritethegeneralformulaeandthefunctionalgroupsoforganiccompoundsin theirsyllabusonachartandrevisit thenamingoforganiccompounds.

● Some studentsmay find it difficult to recall the products of the chemical reactionorbalancetheequation.Theteachermayaskthemtotabulateallthereactionsofaparticularfunctionalgrouptogetheranddrawcorrelationsinthereactions.Correlationsserveasamemorytool.


Assessment technique:ContentBased(orWritingchemicalformula)

Objectives:Toenablethestudentsto

● Writedownthemolecularformulaofhydrocarbons.

● Recognisethefunctionalgroupthroughthenameofthehydrocarbon.

● Appreciatethatifmolecularformulaandfunctionalgrouppresentinthecompoundisknown,structureofthecompoundcanbewritten.

Task: Individual

Procedure:

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

Assessment parameter:Everycorrectanswercarries1mark.

Student Worksheet Time: 10 min.

Instructions:

Writethemolecularformulaanddrawthestructureforthefollowingcompounds.

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Compound Molecular formula Structure

Ethanoicacid

Bromopentane

Butanone

Hexanal

Heptyne


● Somestudentsmaynotbeabletorecallthemolecularformulaofthecompoundsomaydrawthestructurewrong,Teachermayneedtorepeattherevisionexercise.

● AfewstudentsmaynotcountCarbonofCarboxylgroupinthebasechainandmaywriteethanoicacidasC2H5COOH.Teachermayneedtorevisetheconcept-andexplainthenthatallthecarbonsthatarelinkedtoeachotherinachainwithoutanyheteroatominbetweenaretobecountedinrootchain.

● Somestudentsmayassumethehexanaltobeanalcohol.

● Somestudentsmaynotconsiderthebalanceofcarbonwhilewritingthestructureofcompounde.g.Heptyneandcarbonmaybeforming5bonds.Teacherneedtoexplaintothemthesignificanceofnumberofbondsfermedbyacarbonatom.


Assessment technique:DatabasedWorksheet


● UnderstandtheHomologousseriesanditscharacteristics.

● WritethegeneralformulaofHomologousseries.

● Apply thegeneral formulaofahomologousseries to identifyanycompound inheseries.

Task: Individual

Procedure:

Teachermay give thisworksheet to the students after teaching - learning the concept ofThehomologousseries.

Teachermaygivethefollowinginformationtothestudentsasarecall:-

● AserieswiththehydrocarbonshavingsamefunctionalgroupiscalledHomologousseries.

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● Differenceintheformulaandmolecularmassoftwoconsecutivecompoundsmembersofsame

● Homologousseriesis‘-CH2’and-14urespectively.

● A homologous series can be identified with a general formula which helps in determiningtheothermembersoftheseries.

Assessment parameters:Asindicatedintheworksheet.


Instructions:

Arunwrotefewseriesofhydrocarbonandleftblanksinbetween.Lookatthechemicalformulaintheseriesofhydrocarbonscarefullyandanswerthequestionsthatfollow:

I II III IV VCH4 C2H4 C2H2 CH3OH DC2H6 C3H6 B C2H5OH CH3COOHC3H8 A C4H6 C3H7OH C2H5COOHC4H10 C5H10 C5H8 C C3H7COOH

Ql. WhatisthedifferenceintheformulaandmolecularmassbetweenC2H6&C3H8;C3H8 andC4H10?

Q2. WhataresuchseriesofHydrocarbonscalled?

Q3. SubstitutetheblanksA,B,C,Dwithcorrectchemicalformulaofthecompound.

A. _________________________ B. _________________________

C. _________________________ D. _________________________

Q4. NamethefunctionalgrouppresentintheseriesIV&V.

Q5. Whichisthefirstmemberofthealkaneseries?

Q6. Whatisthegeneralformulaofthehomologousseriesofalkyneandalcohol.

Q7. Name the chemical formula of 6thmember of alkyne series and 15thmember of alcohol series.

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● Somestudentsmaynotbeabletomakeandusethegeneralformulaofhomologousseriesofalkyneandalcohol.Theymaybegivenmorepracticeusingdifferentexamplesfromsameanddifferenthomologousseries.

● SomestudentsmaynottoabletoidentifythecompoundandfunctionalgrouppresentinthatHelpthemtorecallthesame.


Assessment technique:FactsbasedWorksheet


● Learnthebasicfactsaboutcarbonatomlikeelectronicconfiguration,valencyanditscombustion.

● understandtheversatilenatureofcarbonatom.

● Appreciatethatcarbonformscompoundsbysharingelectrons.

● Learnthatalkanesaresaturatedbutalkenesandalkynesareunsaturated

● hydrocarbonswherepairofcarbonsarebondedwithdoubleandtriplecovalentbondrespectively.

Task: Individual

Procedure:

Teachermaygivethisworksheettothestudentsafterdiscussingaboutthenatureofcarbonatomanditsbondingability

Teachermaygivethefollowinginformationtothestudentsasarecall:-

● CompoundsofcarbonandhydrogenarecalledHydrocarbons.

● Carbonformscovalentbondsbysharingtheelectrons.

● Alkanesaresaturatedhydrocarbonswithapairofcarbonatomsbondedtogetherwithdoublebond.

● Alkynesareunsaturatedhydrocarbonswithapairofcarbonatomsondedtogetherwithtriplebond.

● HydrocarbonsoncombustionproduceCO2,H2Oheatandenergy.

● Functionalgroupareatomsorgroupofatomspresentinhydrocarbonwhichdeterminesitschemicalproperties.

Assessment parameters:Asindicatedintheworksheet.(Q1-Q81mark)

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Student Worksheet Time : 10 min

Kunalgotafactsheetaboutcarbonatomwhichhasstormedhisbrainwithmanyquestions.

● Atomicnumberofcarbonis6.

● Itistetravalentinnaturethatiswhyonecarbonatomcombineswith4Hydrogenatomtoformmethane.

● Itcanneithergiveelectronortakeelectrontoformacompound.

● Ithasaversetilenatureand formmanyhydrocarbon likealkanesalkenes,alkynes,alcohol,carboxylicacid.

● The chemical properties of hydrocarbon , are determined by the functional grouppresentinit.

Fewofthequestionsarelistedbelowcanyouhelphimwiththeanswers.Tryit

Q1. Whatistheelectronicconfigurationofcarbon?

Q2. Carbonistetravalentinnature.Whatdoesitmean?

Q3. Whatisthevalanceofcarboninethane?

Q4. Carbonneithergiveselectronortakeselectronthenhowdoesitcompleteitsoctetandwhatisthetypeofbondtoformed.

Q5. Whatisahydrocarbon?

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Q6. Whatisthedifferencebetweenalkanesandalkenes?

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

Q8. Whatisafunctionalgroup?

Q9. Whydoescarbonformmanycompounds?(Givetworeasons)

1.

2.


● A fewstudentsmaybepuzzled tofindout thevalenceof carbon in ether.Teachermayneedtoexplain.Ascarbonthatvalenceofcarbonneverchanges(ValenceistheCapacitytoformbondshasfourelectroninoutermostshellitsvaluanceis4)

● A few students may write that alkanes are saturated and alkenes are unsaturatedhydrocarbonoralkeneshaveonepairofcarbonatomsbondedwithdoublebond.

● AfewstudentsmaynotcorrelatethatoneofthemajorcomponentofhydrocarboniscarbonandthereforetheircombustionalsoleadstotheproductionofCO2andH2OheatandlightTeachermayhelpthemtounderstand.


Assessment technique:FormulaBasedWorksheet(Brainstorming)

Objectives:Toenablethelearnersto

● Learnthemolecularformulaofahydrocarbonandwithitsstructureandversa.

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● Establish the relation betweenHydrocarbon’smolecular formula and structure andname

● Applytheconceptofnomenclatureofhydrocarbon.

Task : Individual

Procedure:

TeachermaygivethisworksheettothestudentstoaccesstheirunderstandingofNomenclatureofhydrocarbonsandskillofdrawingthestructureofthehydrcabon,

Assessment parameter:Eachquestioncarries2marks


Instructions:

Givenbelowarethename,molecularformulaandstructureofafewhydrocarbons.Inoneofthethreecolumns,thereissomeerror.Identifythewrongentryandwritethecorrectanswerintheboxgivenbeside.

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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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)andsomaynotfindanyerrorinquestion5.Theyneedtoexplainthesame.


Assessment technique:Contentbased


● understandandlearnthechemicalpropertiesofHydrocarbons..

● Identifythereactantsusedandproductsformedindifferentreactions.

Task: Individual

Procedure:

Teacher may give this worksheet to the students after teaching - learning the properties ofHydrocarbons.Assessmentparameter-1markforeachcorrectanswer

Student Worksheet

Instructions:

Mr.Puriexplained thechemicalpropertiesofhydrocarbons to studentsandwrote thechemicalequationsforthereactions.Heaskedthestudentstonotethemintheirnotebooks.Suddenlythebellrang.Ashemovedout,Rishelrubbedafewcompoundsfromtheblackboard.Nowstudentsareinafuss.Canyouhelptheminplacingchemicalformulaofcorrectcompoundtocompletethechemicalequationforthereactions:

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Try–

1. CH4+O2 _________________+H2O+heatandlight

AlkalineKMnO42. CH3–CH2–OH _________________

HH

NiCatalyst | |

3. _________________ R—C—C—R | | RR

Sunlight4. CH4+_________ CH3Cl+HCl

5. CH3CH2OH+2Na _______________

Hot.Conc.H2SO46. CH3CH2OH _______________

Acid7. CH3CH2OH+CH3COOH _______________

8. CH3CH2COOC2H5+NaOH _______________+C2H5OH

9. CH3COOH+_______________ CH3COONa+H2O

10. CH3COOH+NaHCO3 CH3COONa+H2O+_______________


● Somestudentsmayfinditdifficulttoidentifytheproductorguessthereactantusedinthe chemical reaction.

● Teachermayhelpthemrecallthelearningandrepheattherevisionexcerise.


Assessment technique: Matchthecolumn


● learnthenomenclatureofthehydrocarbonsapplytheunderstandingoftechniqueofnamingofhydrocarbons

● Identifythereactantsusedandproductsformedindifferentreactions.

Task : Individual

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Procedure:

● Teacher may give this worksheet to the students after teaching - learning ofNomenclatureofthehydrocarbons.Followingpointsmayberecalledinconcernwiththenomenclatureofhydrocarbons.

● Carboninthebasicchainwithfunctionalgroupisidentifiedandnamedusingsuitableprefixorsuffixforthefunctionalgroupe.g.ifitisalcoholsuffixusedis‘ol’andifaldehydesuffixusedis‘ol’.

● Tonameacyclicalkanesuffixusediscyclo.

● C6H6isbenzene.

Assessment parameter:1markforeverycorrectmatch.


Instructions:

MatchthestructuresofhydrocarbonsgivenincolumnBwiththeirIUPACnamesincolumnCandwritethecorrespondings.no.numbertothecorrectnameincolumnA

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● Somestudentsmaynotrecall theprefixforaparticularnumberofcarbonandmaynamethebasechainwrong.

● Somestudentsmayconfusebetweentheprefix‘al’isforalcohol’.

● Afewstudentsmaynotdifferentiatethestructurecyclohexaneandbenzene.

● Afewstudentsmaynotcountthecarbonofcarboxylgroupinthebasechain.Teachermayrepeattherevisionexercise.


Assessment technique:Matchthecolumn


● Understandthenomenclatureofthehydrocarbons.

● Identifythenameofahydrocarbon.

● AppreciatethegeneralformulaofaHomologousseries.

Task: Individual

Procedure:

Teachermaygivethisworksheettothestudentstopracticethenomenclatureofthehydrocarbonsafterteachingthesame.

TypesofbondsanduseofgeneralformulaofaHomologousseriesshouldberecalledpriortothat.

● GeneralformulaofAlkanesseriesisCnH2n+2.lnitallthebondsaresingle.

● GeneralformulaofAlkenesisCnH2n.Itcontainsonedoublebond.

● GeneralformulaofAlkynesseriesisCnH2n–2.Itcontainsonetriplebond.

Assessment parameter:

1mark for every correctmatch and onemark for completing and verifying themagic squarecorrectly.


Instructions:

Putthenumberofthehintfromthelistintothesquarewithappropriatematch.Checkyouranswerbyaddingthenumberstoseeifallthesumoftherowsbothacrossanddownadduptothesamenumber,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,confusionmaybe between methanol and methanal.

● Studentscancheckthemselvesbyaddingthenumberintherowsandthinkovertheansweragainorteachermayhelpthemtorecall.

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

Period Classification of Elements Chapter 5

Assesment Technique: DataBasedWorksheet

Objectives:Toenablethestudentsto-

● LearnthesalientfeaturesoftheModernPeriodictable.

● Understandthetrendsofdifferentpropertiesontheperiodictable.

Task: Individual

Procedure:

● ThisworksheetmaybegiventothestudentsafterrecallingthesalientfeaturesoftheperiodictableusingachartdisplayingModernPeriodicTable.

● Thevalenceelectronschangeacrossaperiodbutremainssameinthegroupsandsothevalency.

● Atomicsizedecreasesacrossaperiodbutincreasesdownthegroup.

● Metalliccharacterdecreasesacrossaperiodbutincreasesdownthegroup.

● Nonmetalliccharacterincreasesacrossaperiodbutdecreasesdownthegroup.

Assessment Parameter

½markforeachcorrectanswer

Student Worksheet

ReadthefollowinglineswrittenabouttheModernPeriodicTableandfillintheblanks

IamtheModernPeriodicTable,whereelementsarearrangedonthebasisof______________.I have ______________ Horizontal rows called______________ and ____________verticalcolumnsarecalled______________.Myfirstperiodisveryshortwith__________elements and2 and3Periodcontain____________elements, 4 and5has____________elements. 6 period has____________elements but 7 period is____________.With spaceformore elements. 17 group is of____________ 18 is of____________.Atomic size ofmyelements____________across theperiodbut____________down thegroupsameasthemetallic character but the nonmetallic character is____________to that Number ofvalenceelectrons____________acrosstheperiodsovariesthevalencybutvalencyoftheelementsis____________inagroup.AllthepropertiesofelementsarethePeriodicfuctionof____________.

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


● Afewstudentsmaynotrecollectthesalientfeaturesofthemodernperiodictable.

● thetablecanbedisplayedforthehelp.

● Afewstudentsmaynotrecallthetrendindifferentproperties.

● Teachermayexplainthesameagain.

● TeachermaysuggestthestudentstolearnthePoem.

Period Classification of Elements Class 5

Assesiytent Technique:Diagram/(PeriodicTable)BasedWorksheet

Objectives:Toenablethestudentsto-

● Appreciatetheperiodictrendsinpropertiesofelements.

● Learnsalientfeaturesofnewperiodictable.

● StudyandanalysethegiventablefortheplacementandpropertiesofelementsintheModernPeriodicTable.

Task: Individual

Procedure:

The teacher, may give the following worksheet after the teaching-learning about the modernperiodic table. The following informationmay be recalledwith the students before they startworkingontheworksheet:

● Elementsof1stgrouparecalledalkalimetals,

● 2ndgroupelementsarecalledalkalineEarthmetals,

● Elements of group 17 are called Halogens and that of group 18, are callednoblegases.

● Atomicnumberofelementsincreasesfromlefttorightintheperiodandtoptobottominthegroupinperiodictable.,

● Valency(thecombiningcapacity)ofanelementcanbe.determinedby-

1. Thenumberof,valenceelectronsifthenumberisequaltoorlessthan4.

2. (8-Valenceelectrons)ifthenumberofvalenceelectronsismorethan4.

3. Thegroupnumberforelementsofgroup1and2.

Metals and Non-metals Chapter 3 · 2016-10-31 · metals, their compounds and gases evolved during...

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Transcript of Metals and Non-metals Chapter 3 · 2016-10-31 · metals, their compounds and gases evolved during...