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 3 Method 2

Mass

Time Time Time

Volume Pressure

• Rate = Δ vol CO2 over time

• Volume recorded • Rate = Δ pressure CO2 over time

• Pressure recorded

Procedure Time/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

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 1g CaCO3 to flask and start stopwatch • Vol recorded every 1 min interval •Repeat using 2M HCI

Method 1 Method 3 Method 2

Mass

Time Time Time

Volume Pressure

• Rate = Δ vol CO2 over time

• Volume recorded • Rate = Δ pressure CO2 over time

• Pressure recorded

Procedure Time/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 3 Method 2

Mass

Time Time Time

Volume Pressure

• Rate = Δ vol CO2 over time

• Volume recorded • Rate = Δ pressure CO2 over time

• Pressure recorded

Procedure Time/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/M S2O3

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 methods

Na2S2O3 + 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/M S2O3

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/M KI

Time/s Rate 1/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 + I2 Iodine Clock Rxn

H2O2 + 2I - + 2H+ → 2H2O + I2

I2 + 2S2O32- → S4O6 2- + 2I -

I2 + starch → Blue black

H2O2 - Oxidising Agent I - - Reducing Agent S203

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 + I2 Iodine Clock Rxn

H2O2 + 2I - + 2H+ → 2H2O + I2

I2 + 2S2O32- → S4O6 2- + 2I -

I2 + starch → Blue black

H2O2 - Oxidising Agent I - - Reducing Agent S203

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

00000 0.2M KI 0.8M 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 Rate 1/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 Agent

I - - Reducing Agent S203

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- + I2

I2 + 2 S2032- → 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 Agent

I - - Reducing Agent S203

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- + I2

I2 + 2 S2032- → 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 KI 00000 00000 0.2M 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 + 2H2O

Rxn: 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

Procedure Absorbance

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 KI Abs

Conc 0.04M KI Abs

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 M

0.4 M 0.6 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 M 0.4 M 0.6 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

Time

0.2 M 0.4 M 0.6 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 4 Unit 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 = k k = 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 = kA k = s-1

Rate vs Conc - proportional

Conc vs Time

ktAA

eAA

ot

kt

ot

]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 added HCI was added

Time taken X fade away

Conc Na2S2O3

Time/s Trial 1 ±0.01

Time/s Trial 2 ±0.01

Time/s Trial 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

00046.0107

05.0

.

timeAve

ConcRate

Cal for Conc 0.05M

4 ways for uncertainty rate

1st method Ave time = (107.00 ± 0.01) % uncertainty time = 9.34 x 10-3 % %∆ Rate = %∆ Time Rate = 0.00046 ± 9.34 x 10-3 % = 0.00046 ± 0.000000043

Too small Poor choice

4th method Uncertainty rate = (Max – min) for rate Rate 1 = Conc/time 1 = 0.05 / 102.96 = 0.00049 Rate 2 = Conc/time 2 = 0.05 / 103.23 = 0.00048 Rate 3 = Conc/ time 3 = 0.05 / 114.80 = 0.00043 Max rate = 0.00049 Min rate = 0.00043 Range = (Max – Min)/2 Range = (0.00049 – 0.00043)/2 = 0.00003 Average rate = (R1 + R2 + R3)/3 = 0.00047 ± 0.00003

Consistent Good choice

3rd method Uncertainty rate = std deviation (for conc 0.05) Rate 1 = Conc/time 1 = 0.05 / 102.96 = 0.00049 Rate 2 = Conc/time 2 = 0.05 / 103.23 = 0.00048 Rate 3 = Conc / time 3 = 0.05 / 114.80 = 0.00043 Average rate = (R1 + R2 + R3)/3 = 0.00047 ± std dev = 0.00047 ± 0.000032

Consistent Good choice

2nd method Using Range (Max – Min) for time Range = (Max – Min) for time/2 Range = (114.80 – 102.96)/2 = 5.92 Ave time = (107.00 ± 5.92) % uncertainty time = 5.5% % ∆Rate = %∆Time Rate = 0.00046 ± 5.5% = 0.00046 ± 0.000026

Consistent Good choice

Determination order : Na2S2O3 + 2HCI → NaCI + H2O + S + SO2

Order of Na2S2O3 Conc Na2S2O3 changes, fix [HCI] = 0.1M

Na2S2O3 added HCI was added

Time taken X fade away

Conc Na2S2O3

Time/s Trial 1 ±0.01

Time/s Trial 2 ±0.01

Time/s Trial 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

00046.000.107

05.0

.

timeAve

ConcRate

Cal for Conc 0.05M

2nd method Using Range (Max – Min) for time Range = (Max – Min)/2 Range = (114.80 – 102.96)/2 = 5.92 Ave time = (107.00 ± 5.92) % uncertainty time = 5.5% % ∆Rate = %∆Time Rate = 0.00046 ± 5.5% = 0.00046 ± 0.000026

Consistent Good choice

Uncertainty rate for conc 0.05M

Conc Na2S2O3

Time/s Trial 1 ±0.01

Time/s Trial 2 ±0.01

Time/s Trial 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

Conc Na2S2O3

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

Conc Na2S2O3

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

Conc Na2S2O3

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)

Conc Na2S2O3

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

Conc Na2S2O3

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 uncertainty 0.00046 – 0.000026 = 0.00044

Highest uncertainty 0.00046 + 0.000026 = 0.00048

Lowest uncertainty 0.0158 – 0.0011 = 0.0147

Lowest uncertainty

Highest uncertainty

Lowest uncertainty

Highest uncertainty

Max order

Min order

Order respect to Na2S2O3 = 2.21 Theoretical order = 2.00 % Error order = 10.7%

Determination order: Na2S2O3 + 2HCI → NaCI + H2O + S + SO2

Conc Na2S2O3

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 = 2.21

Conc 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)/2 Max order = 2.29 Min 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 = 2.21 Theoretical order = 2.00 % Error order = 10.7%

Determination order: Na2S2O3 + 2HCI → NaCI + H2O + S + SO2

Conc Na2S2O3

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 = 2.21

Conc 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%

Conc Na2S2O3

Time/s Trial 1 ±0.01

Time/s Trial 2 ±0.01

Time/s Trial 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