AQA A LEVEL CHEMISTRY YEAR ONE - REQUIRED
PRACTICALS PT 1 QUESTIONS WITH CORRECT
ANSWERS UPDATED .
1a),Describe,how,you,should,weigh,out,a,required,mass,given,a,sample,bottle,,,ANS,-
1a),Weigh,the,sample,bottle,to,2dp
Transfer,mass,to,beaker
Reweigh,sample,bottle
Record,difference,in,mass
1a),Describe,how,you,should,make,up,a,volumetric,solution,from,a,weighed,out,mass,,,ANS,-
1a),Add,100cm3,of,distilled,water,to,the,beaker,
Stir,with,a,glass,rod,to,dissolve,the,solid
Pour,solution,into,a,250cm3,gradated,flask,via,funnel
Rinse,funnel,,beaker,and,glass,rod
Add,washings,to,volumetric,flask
Using,a,dropping,pipette,of,distilled,water,,make,solution,up,to,the,mark,
Invert,flask,several,times
1a),Why,must,the,volumetric,flask,be,inverted,several,times?,,,ANS,-
1a),To,ensure,a,uniform,concentration,of,solution
1a),Why,is,the,beaker,sometimes,heated,when,making,up,a,volumetric,solution?,,,ANS,-
1a),Substance,may,not,dissolve,well,in,COLD,water
1a),To,which,point,should,a,volumetric,flask,be,filled?,,,ANS,-
1a),The,bottom,of,the,meniscus,sits,on,the,line
1a),What,is,the,problem,with,making,up,a,volumetric,solution,of,e.g.,KMnO4,?,,,ANS,-1a),Dark,coloured
Difficult,to,see,meniscus
, 1a),Why,must,hot,solutions,not,be,put,in,a,graduated,flask?,,,ANS,-1a),The,flask,would,expand
The,volume,would,be,incorrect
1b),Describe,how,you,would,set,up,the,equipment,for,an,acid-base,titration,,,ANS,-
1b),Rinse,all,equipment,with,distilled,water,and,solutions,that,are,to,be,added,to,them
Pipette,25cm3,of,alkali,into,conical,flask
Touch,surface,of,alkali,with,pipette
Fill,burette,with,acid,
Add,a,few,drops,of,indicator
1b),Describe,how,you,would,carry,out,an,acid-base,titration,(equipment,already,set,up),,,ANS,-
1b),Note,the,burette,reading,
Add,acid,to,alkali,and,swirl,conical,flask
Near,the,end,point,add,the,acid,dropwise
Note,the,burette,reading,
Repeat,titration,until,2,concordant,results
1b),What,are,concordant,results?,,,ANS,-1b),2,readings,that,are,within,0.1,of,each,other
1b),Why,must,you,touch,the,surface,of,the,pipette,with,the,solution,you,are,filling,it,with?,,,ANS,-
1b),To,ensure,the,correct,amount,is,added
The,pipette,calibration,assumed,all,the,pipette,is,filled,(no,air,gaps)
1b),Why,must,you,only,add,a,few,drops,of,indicator?,,,ANS,-1b),Usually,weak,acids
Too,many,drops,affect,titre
1b),Why,must,you,take,the,funnel,out,of,the,burette,before,a,titration?,,,ANS,-
1b),Small,drops,of,the,liquid,might,fall,from,the,funnel,into,the,burette,solution
Lead,to,a,smaller,titre,(inaccurate)
PRACTICALS PT 1 QUESTIONS WITH CORRECT
ANSWERS UPDATED .
1a),Describe,how,you,should,weigh,out,a,required,mass,given,a,sample,bottle,,,ANS,-
1a),Weigh,the,sample,bottle,to,2dp
Transfer,mass,to,beaker
Reweigh,sample,bottle
Record,difference,in,mass
1a),Describe,how,you,should,make,up,a,volumetric,solution,from,a,weighed,out,mass,,,ANS,-
1a),Add,100cm3,of,distilled,water,to,the,beaker,
Stir,with,a,glass,rod,to,dissolve,the,solid
Pour,solution,into,a,250cm3,gradated,flask,via,funnel
Rinse,funnel,,beaker,and,glass,rod
Add,washings,to,volumetric,flask
Using,a,dropping,pipette,of,distilled,water,,make,solution,up,to,the,mark,
Invert,flask,several,times
1a),Why,must,the,volumetric,flask,be,inverted,several,times?,,,ANS,-
1a),To,ensure,a,uniform,concentration,of,solution
1a),Why,is,the,beaker,sometimes,heated,when,making,up,a,volumetric,solution?,,,ANS,-
1a),Substance,may,not,dissolve,well,in,COLD,water
1a),To,which,point,should,a,volumetric,flask,be,filled?,,,ANS,-
1a),The,bottom,of,the,meniscus,sits,on,the,line
1a),What,is,the,problem,with,making,up,a,volumetric,solution,of,e.g.,KMnO4,?,,,ANS,-1a),Dark,coloured
Difficult,to,see,meniscus
, 1a),Why,must,hot,solutions,not,be,put,in,a,graduated,flask?,,,ANS,-1a),The,flask,would,expand
The,volume,would,be,incorrect
1b),Describe,how,you,would,set,up,the,equipment,for,an,acid-base,titration,,,ANS,-
1b),Rinse,all,equipment,with,distilled,water,and,solutions,that,are,to,be,added,to,them
Pipette,25cm3,of,alkali,into,conical,flask
Touch,surface,of,alkali,with,pipette
Fill,burette,with,acid,
Add,a,few,drops,of,indicator
1b),Describe,how,you,would,carry,out,an,acid-base,titration,(equipment,already,set,up),,,ANS,-
1b),Note,the,burette,reading,
Add,acid,to,alkali,and,swirl,conical,flask
Near,the,end,point,add,the,acid,dropwise
Note,the,burette,reading,
Repeat,titration,until,2,concordant,results
1b),What,are,concordant,results?,,,ANS,-1b),2,readings,that,are,within,0.1,of,each,other
1b),Why,must,you,touch,the,surface,of,the,pipette,with,the,solution,you,are,filling,it,with?,,,ANS,-
1b),To,ensure,the,correct,amount,is,added
The,pipette,calibration,assumed,all,the,pipette,is,filled,(no,air,gaps)
1b),Why,must,you,only,add,a,few,drops,of,indicator?,,,ANS,-1b),Usually,weak,acids
Too,many,drops,affect,titre
1b),Why,must,you,take,the,funnel,out,of,the,burette,before,a,titration?,,,ANS,-
1b),Small,drops,of,the,liquid,might,fall,from,the,funnel,into,the,burette,solution
Lead,to,a,smaller,titre,(inaccurate)
