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Chemistry PEKA Form 5Topic :Rate of Reaction Experiment No:
........1.2........
Aim To investigate the effect of concentration on the rate of
reaction.
Problem statement How does the concentration of a reactant
affect the rate of reaction?
Hypothesis The more concentrated the sodium thiosulphate
solution, the higher the rate of reaction.
Variables Manipulated variable :
___________________________________esponding variable : Time ta!en
for the cross "#" to disappear from the sight.
$ontrolled variable : $oncentration and volume of dilute
sulphuric acid , temperature
of the solution
Materials %.2 mol dm&'1() cm'sodium thiosulphate solution,
1.% mol dm&'2) cm'sulphuric acid,
distilled water *% cm', white paper mar!ed "#" at the centre
Apparatus )% cm'measuring c+linder, 1% cm'measuring c+linder,
1)% cm'conical flas!, and stop
watch
Procedure 1. )% cm'of 2.% mol dm&'sodium thiosulphate is
measured using measuring c+linder and
poured into a conical flas!.
2. piece of paper mar!ed "#" is placed under the conical
flas!.
. ) cm'of 1.% mol dm&'sulphuric acid is measured and poured
into the conical flas!.
!. -topwatch is started immediatel+.
". The miture in the conical flas! is swirled and placed it on
the paper mar!ed "#" .
#. Mar! "#" is observed verticall+ from the top through the
solution.
$. Time,t is recorded for the mar! "#" to disappear from
sight.
%. The eperiment is repeated four more times using different
volumes of %.2 mol dm&'sodium
thiosulphate solution to be diluted with different volumes of
distilled water as shown inTable 1.
&ata
'ommunication
(raph of
$oncentrationagainst time
)et Volume of *+2
mol dm,sodium
thiosulphate
solution- cm
Volume of
distilled
.ater- cm
Volume of
1+* mol dm,
sulphuric
acid- cm
Total /olume
of reactin0
mixture- cm
/ )% % ) ))
// (% 1% ) ))
// '% 2% ) ))
/0 2% '% ) ))
0 1% (% ) ))
)et Volume of
*+2 mol dm,
sodium
thiosulphate
solution- cm
Volume of
distilled
.ater- cm
Volume of
1+* mol dm,
sulphuric
acid- cm
Time
taen-s
1 -
Time
1s
/ )% % )
// (% 1% )
// '% 2% )
/0 2% '% )
0 1% (% )
8/13/2019 78491801 F5 PEKA 1 Concentration
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&ra. 0raph 3 use full 0raph paper4
(raph of $oncentration against 1time
&ra. 0raph 3 use full 0raph paper4
5nterpretin0 data 1. $oncentration of sodium thiosulphate
solution in the reacting miture.
2. ased on the graphs,when the concentration of sodium
thiosulphate is higher, the time
ta!en for the mar! "#" to disappear from sight is
_____________.'. The rate of reaction directl+ proportional to the
concentration of sodium thiosulphate
solution used.
'onclusion The h+pothesis is accepted.
EN&
)et 'oncentration of sodium
thiosulphate- mol dm,
/%.2#)% 3 %.1*
))
//%.2#(% 3 %.1)
))
///
%.2#'% 3 %.11
))
/0%.2#2% 3 %.%4
))
0
%.2#1% 3 %.%( ))
