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Prepared by Lawrence Kok
IB Chemistry Kinetics and methods to measure for IA and uncertainty calculation for order.
Techniques Used to measure Rate of Rxn
Rxn: CaCO3 with HCI measured using THREE diff methods CaCO3 + 2HCI → CaCI2 + CO2 + H2O
• Rate = Δ mass CaCO3 over time• Initial mass recorded
• CaCO3 + 2HCI → CaCI2 + CO2 + H2O • (CaCO3 limiting, HCI excess)• 50ml, 1M HCI into flask • Place on balance• 1g CaCO3, place on balance• Record total mass • Add CaCO3 to flask and start stopwatch • Mass flask recorded every 1 min interval• Repeat using 2M HCI
Method 1 Method 3Method 2
Mass
Time Time Time
Volume Pressure
• Rate = Δ vol CO2 over time• Volume recorded
• Rate = Δ pressure CO2 over time• Pressure recorded
ProcedureTime/m Total
mass(HCI 1M)
Total mass
(HCI 2M)
0 60.00 60.00
1 59.20 58.10
2 58.80 57.70
3 57.50 56.70
4 57.00 55.40
Mass
Time2M HCI
1M HCI
Techniques Used to measure Rate of Rxn
Rxn: CaCO3 with HCI measured using THREE diff methods CaCO3 + 2HCI → CaCI2 + CO2 + H2O
• Rate = Δ mass CaCO3 over time• Initial mass recorded
• CaCO3 + 2HCI → CaCI2 + CO2 + H2O • (CaCO3 limiting, HCI excess)• 50ml, 1M HCI into flask • Add 1g CaCO3 to flask and start stopwatch • Vol recorded every 1 min interval• Repeat using 2M HCI
Method 1 Method 3Method 2
Mass
Time Time Time
Volume Pressure
• Rate = Δ vol CO2 over time• Volume recorded
• Rate = Δ pressure CO2 over time• Pressure recorded
ProcedureTime/m Vol CO2
(HCI 1M)Vol CO2
(HCI 2M)
0 0.0 0.0
1 8.5 14.0
2 15.0 26.5
3 21.0 34.0
4 26.0 39.0
Volume CO2
Time
2M HCI
1M HCI
Techniques Used to measure Rate of Rxn
Rxn: CaCO3 with HCI measured using THREE diff methods
CaCO3 + 2HCI → CaCI2 + CO2 + H2O
• Rate = Δ mass CaCO3 over time• Initial mass recorded
• CaCO3 + 2HCI → CaCI2 + CO2 + H2O • (CaCO3 limiting, HCI excess)• 50ml, 1M HCI into flask • Add 1gCaCO3 to flask and start stopwatch • Press recorded every 1 min interval• Repeat using 2M HCI
Method 1 Method 3Method 2
Mass
Time Time Time
Volume Pressure
• Rate = Δ vol CO2 over time• Volume recorded
• Rate = Δ pressure CO2 over time• Pressure recorded
ProcedureTime/m Pressure
CO2(HCI 1M)
Pressure CO2
(HCI 2M)
0 101.3 101.3
1 102.4 103.4
2 103.5 105.6
3 110.3 115.2
4 113.5 118.2
Pressure CO2
Time
2M HCI
1M HCI
Techniques Used to measure Rate of Rxn
• Rate = Δ mass Sulfur over time
Method 1 Method 2
Mass
Time Time
Light Intensity
• Rate = Δ light intensity over time• Light intensity recorded
Procedure Conc/MS2O3
2- Time/s Rate
1/Time
0.2 80.8 1/80.8 = 0.0123
0.4 40.2 1/40.2 = 0.0248
0.6 25.2 1/25.2 = 0.0396
0.8 20.5 1/20.5 = 0.0487
1.0 18.2 1/18.2 = 0.0550
Rate = 1/time
Conc
Rxn: Na2S2O3 with HCI measured using TWO diff methodsNa2S2O3 + 2HCI → 2NaCI2 + SO2 + H2O + S
• Na2S2O3 + 2HCI → 2NaCI2 + SO2 + H2O + S • (Na2S2O3 limiting, HCI excess)• 50ml 0.2M HCI into conical flask• Place on top of paper with cross X• Pour 5ml 0.1M Na2S2O3 into flask• Record time for X to disappear• Repeat with diff S2O3
2- conc
Light sensor
Light source
0.2 0.4 0.6 0.8
• Na2S2O3 + 2HCI → 2NaCI2 + SO2 + H2O + S • (Na2S2O3 limiting, HCI excess)• Pipette 1ml 0.2M S2O3
2- into cuvette• Pipette 0.1ml 0.1M HCI into cuvette• Mix and start light sensor• Record time for light intensity to drop• Repeat with diff S2O3
2- conc
Techniques Used to measure Rate of Rxn
• Rate = Δ mass Sulfur over time
Method 1 Method 2
Mass
Time Time
Light Intensity
• Rate = Δ light intensity over time• Light intensity recorded
Procedure Conc/MS2O3
2- Time/s Rate
1/Time
0.2 80.8 1/80.8 = 0.0123
0.4 40.2 1/40.2 = 0.0248
0.6 25.2 1/25.2 = 0.0396
0.8 20.5 1/20.5 = 0.0487
1.0 18.2 1/18.2 = 0.0550
Rate = 1/time
Rxn: Na2S2O3 with HCI measured using TWO diff methods
Na2S2O3 + 2HCI → 2NaCI2 + SO2 + H2O + S
Light source
Light sensor
Light intensity
0.8M S2O3
2- 1M S2O3
2-
Conc
0.2 0.4 0.6 0.8 18.2 20.3 time
• H2O2 + 2KI + 2HCI → 2KCI + 2H2O + I2 (KI limiting, H2O2 excess)• Pipette 5ml 3% H2O2, 5ml 0.1M HCI into flask• Add starch, 1ml 0.1M S2O3 to flask• Place on white paper with cross X • Pipette 5 ml 0.1M KI into flask• Record time for X to disappear• Repeat with diff KI conc
Techniques Used to measure Rate of Rxn
Method 1 Method 2
Mass iodine produced
Time Time
Absorbance
• Rate = Δ Absorbance over time• Absorbance recorded
Procedure Conc/MKI
Time/s Rate1/Time
0.00625 80.8 1/80.8 = 0.0123
0.0125 40.2 1/40.2 = 0.0248
0.025 25.2 1/25.2 = 0.0396
0.05 20.5 1/20.5 = 0.0487
0.1 18.2 1/18.2 = 0.0550
Rate = 1/time
Conc
Rxn: H2O2 with I - measured using TWO diff methods
H2O2 + 2I- + 2H+ → 2H2O + I2Iodine Clock Rxn
H2O2 + 2I - + 2H+ → 2H2O + I2I2 + 2S2O3
2- → S4O6 2- + 2I -
I2 + starch → Blue black
H2O2 - Oxidising AgentI - - Reducing AgentS203
2- - Reduce I2 to I –I2 - I2 react with starch form blue black• Rate = Δ mass iodine over time
= Disappearance X due to blue black formation
Abs increase when blue black
form
0.025 0.05 0.1
• H2O2 + 2KI + 2HCI → 2KCI + 2H2O + I2 (KI limiting, H2O2 excess)• Pipette 0.5ml 3% H2O2, 0.1M HCI to cuvette• Add starch, 0.1ml 0.1M S2O3 to cuvette• Pipette 0.5ml 0.2M KI to cuvette• Record Abs change• Repeat with diff KI conc
Techniques Used to measure Rate of Rxn
Method 1 Method 2
Mass iodine produced
Time Time
Absorbance
• Rate = Δ Absorbance over time• Absorbance recorded
Procedure Absorbance
Time
Abs increase when blue black
form
Rxn: H2O2 with I - measured using TWO diff methods
H2O2 + 2I- + 2H+ → 2H2O + I2Iodine Clock Rxn
H2O2 + 2I - + 2H+ → 2H2O + I2I2 + 2S2O3
2- → S4O6 2- + 2I -
I2 + starch → Blue black
H2O2 - Oxidising AgentI - - Reducing AgentS203
2- - Reduce I2 to I –I2 - I2 react with starch form blue black• Rate = Δ mass iodine over time
= Disappearance X due to blue black formation
Time Conc KI
(0.2)Abs
Conc KI
(0.4)Abs
Conc KI
(0.6)Abs
Conc KI
(0.8)Abs
0 0.1 0.1 0.1 0.1
2 0.1 0.1 0.1 0.1
4 0.1 0.1 0.1 1.4
6 0.1 0.1 1.2
8 0.1 0.1
10 0.1 1.3
12 0.1
Rate 1/14= 0.07
1/10= 0.1
1/6= 0.16
1/ 4= 0.25
000000.2M KI0.8M KI
4 6 10 12
Techniques Used to measure Rate of Rxn
Method 1 Method 2
Mass iodine produced
Time Time
Absorbance
• Rate = Δ Absorbance over time• Absorbance recorded
Procedure Conc KI/M
Time/s Rate1/Time
0.00625 80.8 1/80.8 = 0.0123
0.0125 40.2 1/40.2 = 0.0248
0.025 25.2 1/25.2 = 0.0396
0.05 20.5 1/20.5 = 0.0487
0.1 18.2 1/18.2 = 0.0550
Rate = 1/time
Conc
Rxn: S2O82- with I - measured using TWO diff methods
Iodine Clock Rxn
S2O82 - Oxidising
AgentI - - Reducing AgentS203
2- - Reduce I2 to I –I2 - I2 react with starch form blue black
• Rate = Δ mass iodine over time = Disappearance X due to blue black formation
Abs increase when blue black
form
S2O82- + 2I - → 2SO4
2- + I2
S2O82- + 2I - → 2SO4
2- + I2I2 + 2 S203
2- → S406 2- + 2I -
I2 + starch → Blue black
• S2O82- + 2I - → 2SO4
2- + I2 (KI limiting, S2O8
2- excess)• Pipette 5ml 0.1M KI, 0.1M S2O3 • Add 1ml starch to flask• Place on white paper with cross X • Pipette 5 ml 0.1M S2O8
2- to flask• Record time for X to disappear• Repeat with diff KI conc
0.0125 0.025 0.05 0.1
• S2O82- + 2I - → 2SO4
2- + I2 (KI limiting, S2O8
2- excess)• Pipette 0.5ml 0.1M KI, 0.1M S2O3 to cuvette• Add 0.1ml starch to cuvette• Pipette 0.5ml 0.1M S2O8
2- to cuvette• Record Abs change• Repeat with diff KI conc
Techniques Used to measure Rate of Rxn
Method 1 Method 2
Mass iodine produced
Time Time
Absorbance
• Rate = Δ Absorbance over time• Absorbance recorded
Procedure
Rxn: S2O82- with I - measured using TWO diff methods
Iodine Clock Rxn
S2O82 - Oxidising
AgentI - - Reducing AgentS203
2- - Reduce I2 to I –I2 - I2 react with starch form blue black
• Rate = Δ mass iodine over time = Disappearance X due to blue black formation
Abs increase when blue black
form
S2O82- + 2I - → 2SO4
2- + I2
S2O82- + 2I - → 2SO4
2- + I2I2 + 2 S203
2- → S406 2- + 2I -
I2 + starch → Blue black
Time Conc KI
(0.2)Abs
Conc KI
(0.4)Abs
Conc KI
(0.6)Abs
Conc KI
(0.8)Abs
0 0.1 0.1 0.1 0.1
2 0.1 0.1 0.1 0.1
4 0.1 0.1 0.1 1.4
6 0.1 0.1 1.2
8 0.1 0.1
10 0.1 1.3
12 0.1
Rate 1/14= 0.07
1/10= 0.1
1/6= 0.16
1/ 4= 0.25
Absorbance
Time
0.8M KI00000000000.2M KI
4 6 10 12
Techniques Used to measure Rate of Rxn
Method 1 Method 2
Time Time
Volume Pressure
• Rate = Δ vol O2 over time• Volume recorded
• Rate = Δ pressure O2 over time• Pressure recorded
Procedure
2H2O2 → O2 + 2H2ORxn: H2O2 with KI (catalyst) measured using TWO diff methods
• 2H2O2 → O2 + 2H2O (H2O2 limiting, KI excess)• Pipette 1ml 1.0M KI to 20ml of 1.5% H2O2 • Vol O2 released recorded at 1 min interval• Repeated using 3% H2O2 conc
Time/m Vol O2(H2O2 1.5%)
Vol O2(H2O2 3.0%)
0 0.0 0.0
1 8.5 14.0
2 15.0 26.5
3 21.0 34.0
4 26.0 39.0
Volume O2
Time
3 %
1.5 %
• 2H2O2 → O2 + 2H2O (H2O2 limiting, KI excess)• Pipette 1ml 1.0M KI to 20ml of 1.5% H2O2 • Pressure O2 released recorded at 1 min interval• Repeat using 3% H2O2 conc
Techniques Used to measure Rate of Rxn
Method 1 Method 2
Time Time
Volume Pressure
• Rate = Δ vol O2 over time• Volume recorded
• Rate = Δ pressure O2 over time• Pressure recorded
Procedure
2H2O2 → O2 + 2H2O
Time
3 %
1.5 %
Time/m Pressure O2(H2O2 1.5%)
Pressure O2
(H2O2 3%)
0 101.3 101.3
1 102.4 103.4
2 103.5 105.6
3 110.3 115.2
4 113.5 118.2
Pressure O2
Rxn: H2O2 with KI (catalyst) measured using TWO diff methods
• Rate = Δ Conc I2 over time• Conc recorded using titration
Techniques Used to measure Rate of Rxn
Method 1 Method 2
Conc iodine produced
Time Time
Absorbance
• Rate = Δ Absorbance over time• Absorbance recorded
ProcedureAbsorbance
Time
Abs increase when iodine
form
2Fe3+ + 2I - → 2Fe2+ + I2
Rxn: Fe3+ + I - measured using TWO diff methods
Fe 3+ - Oxidising Agent
I - - Reducing Agent
• 2Fe3+ + 2I - → 2Fe2+ + I2 • (I - limiting, Fe3+ excess)• Pipette 1.5ml 0.02M Fe3+to cuvette. • Find λ max for Fe3+ (450nm)• Abs vs time , select λ = 450nm• Pipette 1.0ml 0.02M KI to cuvette• Measure abs increase due to I2 formation• Repeat using diff KI conc
Time/s Conc 0.02M KIAbs
Conc 0.04M KIAbs
0 0.240 0.240
1 0.245 0.260
2 0.257 0.330
3 0.300 0.390
4 0.330 0.540
0.04 M
0.02 M
• 2Fe3+ + 2I - → 2Fe2+ + I2 (I - limiting, Fe3+ excess)• Pipette 25ml 0.02M KI /Fe3+ to flask. • Start time• Every 5min, pipette 10ml sol mix to flask • Titrate with S2O3
2-
( I2 form will react with S2O32-)
Amt I2 produced is determine.• I2 + 2S203
2- → S4O62- + 2I – (Mol ratio 1:2)
• Rate = Δ Conc I2 over time• Conc recorded using titration
Techniques Used to measure Rate of Rxn
Method 1 Method 2
Conc iodine produced
Time Time
Absorbance
• Rate = Δ Absorbance over time• Absorbance recorded
Procedure
Conc I2
Time
2Fe3+ + 2I - → 2Fe2+ + I2
Rxn: Fe3+ + I - measured using TWO diff methods
Fe 3+ - Oxidising Agent
I - - Reducing Agent
Time/m
Vol S2O3/ cm3
Conc I2/M
0 0 0
5 6 0.06
10 18 0.18
15 28 0.28
20 28 0.28
25 ml 0.02M KI/Fe3+
10ml removed every 5m
0.2M S2O33-
Contain I2
2S2032- + I2 → S4O6
2- + 2I –
2 mol S2032 – 1 mol I2
0.0012 mol – 0.006 mol I2
Vol S2032- 6.0ml – Amt S203
2- = M x V = 0.2 x 0.006 = 0.0012 mol
Conc I2 = Amt I2/Vol = 0.0006/0.01 = 0.06 M
• I2 + CH3COCH3 → CH3COCH2I + H+ + I – (CH3COCH3 limiting, I2
excess)• Pipette 1ml 0.002M I2 to cuvette. • Abs vs Time (λ max = 520nm)• Pipette 0.4ml 2M HCI and 1ml water to cuvette• Pipette 0.4ml 0.2M CH3COCH3 to cuvette • Record drop in abs over time• Repeat using diff CH3COCH3 conc
• Rate = Δ Conc I2 over time• Conc recorded
Techniques Used to measure Rate of Rxn
Method 1 Method 2
Conc iodine
Time Time
Absorbance I2
• Rate = Δ Absorbance over time• Absorbance recorded
Procedure
Time
Abs decrease I2 consumed
I2 + CH3COCH3 → CH3COCH2I + H+ + I -
Rxn: I2 + CH3COCH3 measured using TWO diff methods
Time Conc (0.2M)
Abs
Conc (0.4M)
Abs
Conc (0.6M)
Abs
0 2.00 2.00 2.00
2 1.86 1.76 1.52
4 1.75 1.54 1.20
6 1.57 1.24 0.78
8 1.23 1.23 0.56
10 1.10 0.78 0.40
Rate Gradient
Time 0
Gradient
Time 0
Gradient
Time 0
Absorbance I2
0.2 M0.4 M0.6 M
Conc CH3COCH3
Rate
• Rate = Δ Conc I2 over time• Conc obtain from std calibration plot
Techniques Used to measure Rate of Rxn
Method 1 Method 2
Conc iodine
Time Time
Absorbance I2
• Rate = Δ Absorbance over time• Absorbance recorded
Procedure
I2 + CH3COCH3 → CH3COCH2I + H+ + I -
Rxn: I2 + CH3COCH3 measured using TWO diff methods
Time Conc I2(0.2M)
Abs
Conc I2(0.4M)
Abs
Conc I2(0.6M)
Abs
0 2.00 2.00 2.00
2 1.86 1.76 1.52
4 1.75 1.54 1.20
6 1.57 1.24 0.78
Absorbance I2
0.2 M0.4 M0.6 M
Conc I2• I2 + CH3COCH3 → CH3COCH2I + H+ + I – (CH3COCH3 limiting, I2
excess)• Pipette 1ml 0.002M I2 to cuvette. • Prepare std calibration plot Abs vs I2 conc• Abs vs Time (λ max = 520nm)• Pipette 0.4ml 2M HCI and 1ml water to cuvette• Pipette 0.4ml 0.2M CH3COCH3 to cuvette • Record drop in abs over time• Repeat using diff I2 conc
Convert Abs I2 to conc I2 using std calibration curve
Time0.2 M0.4 M0.6 M
Conc I2 Abs
0 0
0.125 0.3
0.25 0.5
0.5 0.7
1.0 1.1
Std calibration curve
Time
Graphical Representation of Order :ZERO, FIRST and SECOND order
ZERO ORDER FIRST ORDER SECOND ORDER
Rate – 2nd order respect to [A]Conc x2 – Rate x 4Unit for k Rate = k[A]2
Rate = kA2
k = M-1s-1
Rate
Conc reactant
Rate
Conc reactant Conc reactant
Conc Conc Conc
Time Time Time
Time
Conc reactant
Rate
Time
ln At
Time
1/At
ktAA ot ][][
Rate = k[A]0
Rate independent of [A]Unit for k Rate = k[A]0
Rate = kk = Ms-1
Rate vs Conc – Constant
Conc vs Time – Linear
Rate = k[A]1
Rate - 1st order respect to [A]Unit for k Rate = k[A]1
Rate = kAk = s-1
Rate vs Conc - proportional
Conc vs Time
ktAAeAA
ot
ktot
]ln[]ln[][][
[A]t
[A]o
ktAA ot
][1
][1
ln Ao
1/Ao
Conc at time t Conc at time t
Using 2nd method to find order
Determination order: Na2S2O3 + 2HCI → NaCI + H2O + S + SO2
Order of Na2S2O3 Conc Na2S2O3 changes, fix [HCI] = 0.1M
Na2S2O3 addedHCI was added
Time taken X fade away
ConcNa2S2O3
Time/sTrial 1±0.01
Time/sTrial 2±0.01
Time/sTrial 3±0.01
Average time
Rate
0.05 102.96 103.23 114.80 107.00 0.00046
0.10 45.43 44.08 38.35 42.62 0.0023
0.15 27.36 27.13 26.36 26.95 0.0055
0.20 18.06 18.57 17.53 18.05 0.0111
0.25 15.26 15.44 16.88 15.86 0.0158
Result expt
00046.010705.0
.
timeAveConcRate
Cal for Conc 0.05M
4 ways for uncertainty rate
1st methodAve time = (107.00 ± 0.01)% uncertainty time = 9.34 x 10-3 %%∆ Rate = %∆ TimeRate = 0.00046 ± 9.34 x 10-3 % = 0.00046 ± 0.000000043
Too smallPoor choice
4th methodUncertainty rate = (Max – min) for rateRate 1 = Conc/time 1 = 0.05 / 102.96 = 0.00049Rate 2 = Conc/time 2 = 0.05 / 103.23 = 0.00048Rate 3 = Conc/ time 3 = 0.05 / 114.80 = 0.00043Max rate = 0.00049Min rate = 0.00043Range = (Max – Min)/2 Range = (0.00049 – 0.00043)/2 = 0.00003Average rate = (R1 + R2 + R3)/3 = 0.00047 ± 0.00003
ConsistentGood choice
3rd methodUncertainty rate = std deviation (for conc 0.05)Rate 1 = Conc/time 1 = 0.05 / 102.96 = 0.00049Rate 2 = Conc/time 2 = 0.05 / 103.23 = 0.00048Rate 3 = Conc / time 3 = 0.05 / 114.80 = 0.00043Average rate = (R1 + R2 + R3)/3 = 0.00047 ± std dev = 0.00047 ± 0.000032
ConsistentGood choice
2nd methodUsing Range (Max – Min) for timeRange = (Max – Min) for time/2Range = (114.80 – 102.96)/2 = 5.92Ave time = (107.00 ± 5.92)% uncertainty time = 5.5%% ∆Rate = %∆TimeRate = 0.00046 ± 5.5% = 0.00046 ± 0.000026
ConsistentGood choice
Determination order : Na2S2O3 + 2HCI → NaCI + H2O + S + SO2
Order of Na2S2O3 Conc Na2S2O3 changes, fix [HCI] = 0.1M
Na2S2O3 addedHCI was added
Time taken X fade away
ConcNa2S2O3
Time/sTrial 1±0.01
Time/sTrial 2±0.01
Time/sTrial 3±0.01
Average time
Rate
0.05 102.96 103.23 114.80 107.00 0.00046
0.10 45.43 44.08 38.35 42.62 0.0023
0.15 27.36 27.13 26.36 26.95 0.0055
0.20 18.06 18.57 17.53 18.05 0.0111
0.25 15.26 15.44 16.88 15.86 0.0158
Result expt
00046.000.10705.0
.
timeAveConcRate
Cal for Conc 0.05M
2nd methodUsing Range (Max – Min) for timeRange = (Max – Min)/2Range = (114.80 – 102.96)/2 = 5.92Ave time = (107.00 ± 5.92)% uncertainty time = 5.5%% ∆Rate = %∆TimeRate = 0.00046 ± 5.5% = 0.00046 ± 0.000026
ConsistentGood choice
Uncertainty rate for conc 0.05M
ConcNa2S2O3
Time/sTrial 1±0.01
Time/sTrial 2±0.01
Time/sTrial 3±0.01
Average time
± Time Range (Max- Min)/2
% ±Time Rate(±rate)
0.05 102.96 103.23 114.80 107.00 (114.8-102.96)/2 = 5.92
5.5% 0.00046 ±0.000026
0.10 45.43 44.08 38.35 42.62 (45.43 – 38.35)/2 = 3.54
8.3% 0.0023 ±0.00027
0.15 27.36 27.13 26.36 26.95 (27.13 – 26.36)/2 = 0.50
1.8% 0.0055 ±0.00022
0.20 18.06 18.57 17.53 18.05 (18.06 – 17.53)/2 = 0.52
2.8% 0.0111 ±0.0006
0.25 15.26 15.44 16.88 15.86 (16.88 – 15.26)/2 = 0.81
5.1% 0.0158 ±0.0011
Determination order: Na2S2O3 + 2HCI → NaCI + H2O + S + SO2
Plot of Conc vs Rate
ConcNa2S2O3
Rate(±rate)
0.05 0.00046 ±0.0000026
0.10 0.0023 ±0.00027
0.15 0.0055 ±0.00022
0.20 0.0111 ±0.0006
0.25 0.0158 ±0.0011
Order for Na2S2O3 (fix conc HCI)Let Rate = k[Na2S2O3]x [HCI] y
Rate
Conc Na2S2O3
Uncertainty rate
Conc Na2S2O3
Rate
Best fit Order = 2.21
Best fit Order = 2.21
Max fit Order = 2.29
Min fit Order = 2.12
Lowest uncertainty (Lowest Conc) to Highest uncertainty (Highest Conc)
Highest uncertainty (Lowest Conc) to Lowest uncertainty (Highest Conc)
Max order
Min order
Determination order: Na2S2O3 + 2HCI → NaCI + H2O + S + SO2
ConcNa2S2O
3
Rate(±rate)
0.05 0.00046 ±0.0000026
0.10 0.0023 ±0.00027
0.15 0.0055 ±0.00022
0.20 0.0111 ±0.0006
0.25 0.0158 ±0.0011
ConcNa2S2O
3
Rate(±rate)
0.05 0.00044
0.10 0.00221
0.15 0.0055
0.20 0.0114
0.25 0.017
Max order
Max fit Order = 2.29
Max order – Lowest uncertainty (Lowest Conc) to Highest uncertainty (Highest Conc)
ConcNa2S2O
3
Rate(±rate)
0.05 0.00046 ±0.0000026
0.10 0.0023 ±0.00027
0.15 0.0055 ±0.00022
0.20 0.0111 ±0.0006
0.25 0.0158 ±0.0011
Min order
ConcNa2S2O
3
Rate(±rate)
0.05 0.00048
0.10 0.00248
0.15 0.0055
0.20 0.0108
0.25 0.0147
Conc Na2S2O3
Conc Na2S2O3
Rate
Rate
Min fit Order = 2.12
Min order – Highest uncertainty (Lowest Conc) to Lowest uncertainty (Highest Conc)
Highest uncertainty 0.0158 + 0.0011 = 0.017
Lowest uncertainty0.00046 – 0.000026= 0.00044
Highest uncertainty0.00046 + 0.000026= 0.00048
Lowest uncertainty0.0158 – 0.0011= 0.0147
Lowest uncertainty
Highest uncertainty
Lowest uncertainty
Highest uncertainty
Max order
Min order
Order respect to Na2S2O3 = 2.21Theoretical order = 2.00% Error order = 10.7%
Determination order: Na2S2O3 + 2HCI → NaCI + H2O + S + SO2
ConcNa2S2O3
Rate(±rate)
0.05 0.00046 ±0.0000026
0.10 0.0023 ±0.00027
0.15 0.0055 ±0.00022
0.20 0.0111 ±0.0006
0.25 0.0158 ±0.0011
Order for Na2S2O3 (fix conc HCI)Let Rate = k[Na2S2O3]x [HCI] 1
Order x = 2.21Conc Na2S2O3
Rate Best fit Order = 2.21
Max fit Order = 2.29
Min fit Order = 2.12
Uncertainty order = (Max order – Min order)/2
%7.10%10000.2
)00.221.2(
± Uncertainty for order = (Max – Min order)/2Max order = 2.29Min order = 2.12± Uncertainty order(Max – Min)/2 = ( 2.29 – 2.12)/2 = 0.09
± Uncertainty order = 2.21 ± 0.09% uncertainty order = (0.09/2.21) x 100 % = 4%
% Error order = 10.7%
% Uncertainty(Random Error)
% Uncertainty(Systematic Error)
4%
% Error = % Random + % Systematic error error% Systematic = (10.7 – 4 )= 6.7% error
Correct Method !
Order respect to Na2S2O3 = 2.21Theoretical order = 2.00% Error order = 10.7%
Determination order: Na2S2O3 + 2HCI → NaCI + H2O + S + SO2
ConcNa2S2O3
Rate(±rate)
0.05 0.00046 ±0.0000026
0.10 0.0023 ±0.00027
0.15 0.0055 ±0.00022
0.20 0.0111 ±0.0006
0.25 0.0158 ±0.0011
Order for Na2S2O3 (fix conc HCI)Let Rate = k[Na2S2O3]x [HCI] 1
Order x = 2.21Conc Na2S2O3
Rate
Best fit Order = 2.21
% Uncertainty rate = % Uncertainty time = 5.5%
%7.10%10000.2
)00.221.2(
% Error order = 10.7%
% Uncertainty(Random Error)
% Uncertainty(Systematic Error)
5.5%
ConcNa2S2O
3
Time/sTrial 1±0.01
Time/sTrial 2±0.01
Time/sTrial 3±0.01
Average time
± Time Range (Max- Min)/2
% ±Time
0.05 102.96 103.23 114.80 107.00 (114.8-102.96)/2 = 5.92
5.5%
0.10 45.43 44.08 38.35 42.62 (45.43 – 38.35)/2 = 3.54
8.3%
0.15 27.36 27.13 26.36 26.95 (27.13 – 26.36)/2 = 0.50
1.8%
0.20 18.06 18.57 17.53 18.05 (18.06 – 17.53)/2 = 0.52
2.8%
0.25 15.26 15.44 16.88 15.86 (16.88 – 15.26)/2 = 0.81
5.1%Wrong Method !
% Error = % Random + % Systematic error error% Systematic = (10.7 – 5.5)= 5.2 % error
Acknowledgements
Thanks to source of pictures and video used in this presentation
Thanks to Creative Commons for excellent contribution on licenseshttp://creativecommons.org/licenses/
Prepared by Lawrence Kok
Check out more video tutorials from my site and hope you enjoy this tutorialhttp://lawrencekok.blogspot.com