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FACULTY OF EDUCATION AND LANGUAGES
SEPTEMBER 2014 / SEMESTER 9
HBSC3203_V2 CHEMISTRY II / KIMIA II
MATRICULATION NO : 781117065006001
IDENTITY CARD NO. : 781117065006
TELEPHONE NO. : 019-4355002
E-MAIL : [email protected]
LEARNING CENTRE : PERAK LEARNING CENTER
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HBSC3203_V2 CHEMISTRY II / KIMIA II
Contents
1(a) ..............................................................................................3-4
i. Reactants in solutions react faster at higher concentration.
ii. Raising the temperature increases the rate of reaction.
(b) The reaction between sodium thiosulphate solution and iron (III) nitrate is catalysed by
transition metal ions. Propose an experiment to study the effect of catalyst on the rate of
reaction.
2..................................................................................................5-8
(a) 100 cm3 of alkane X with the general formula CxHy requires 650 cm3 of oxygen for
complete combustion. Deduce the structural formulae for the isomers of X.
(b) By writing the general formula for cyclodiene, deduce the molecular formula of
(i) cylohexadiene
(ii) 2-ethylcyclohexa-1,3 – diene
(c) Propose the reaction mechanism for the following reaction:
(d) Discuss THREE industrial importance of cyclopentane.
REFERENCES..................9
ANSWER
NORHAZRIMELIANA BINTI ABDUL RAHIM 781117065006001
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HBSC3203_V2 CHEMISTRY II / KIMIA II
QUESTION 1
(a)
i. When the concentration increase, more molecules are present, so, they will collide more.
As the concentration increase, the kinetic energy also increase when more collisions
occurs. Consequently, the reaction rate usually increases as the concentrations increases.
ii. Increasing the temperature also increasing the average kinetic energy of its particles.
When the kinetic energy increases, the particles move faster and collide more frequently
and produce greater energy when they collide. So, the reaction rate will increases as the
temperature increases.
(b) Experiment to study the effect of catalyst on the rate of reaction
Title:
The reaction between sodium thiosulphate solutions and iron (III) nitrate is catalysed by different
transition metal ions. The catalysts used are copper (II) sulphate, nickel (II) sulphate, iron (II)
sulphate and cobalt (II) chloride.
Apparatus and chemical
i. Eye protection
ii. Stopwatch
iii. Measuring cylinder
iv. Conical flask
v. Test tube
vi. Cobalt (II) chloride solution
vii. Nickel (II) sulphate solution
viii. Copper (II) sulphate solution
ix. Iron (II) sulphate solution
x. Iron (III) nitrate solution
xi. Sodium thiosulphate solution
Procedure:
NORHAZRIMELIANA BINTI ABDUL RAHIM 781117065006001
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HBSC3203_V2 CHEMISTRY II / KIMIA II
a) Measuring the speed of the reaction without catalysts
i. Put 10mL of iron (III) nitrate in the conical flask
ii. Stand the flask on the white tile
iii. Add 100mL of sodium thiosulphate into the conical flask
iv. Start the stopwatch
v. Stop the stopwatch when the solution goes colourless
vi. Record in the table, the time taken for the solution to go colourless
b) Measuring the speed of the reaction with a catalysts
i. Pour 10mL of iron (III) nitrate into the conical flask
ii. Stand the flask on the white tile
iii. Add 5 drops of nickel (II) sulphate solution
iv. Add 10mL of sodium thiosulphate into the conical flask
v. Start the stopwatch
vi. Record in the table, the time taken for the solution to go colourless
vii. Repeat the experiment using 5 drops of copper (II) sulphate, iron (II) sulphate and cobalt
(II) chloride.
Result:
Fill in the table below
Substance Time (in secs) for solution to
colourless)
No catalyst
Nickel (II) sulphate
Copper (II) sulphate
Iron (II) sulphate
Cobalt (II) chloride
Questions:
NORHAZRIMELIANA BINTI ABDUL RAHIM 781117065006001
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HBSC3203_V2 CHEMISTRY II / KIMIA II
1) What metal compound was the best catalyst?
2) Why were only very dilute solutions of metal compound used?
3) State 3 ways in which this reaction could be slowed down
Question 2
(a) CX H y+O2→ CO2+H 2 O
Volume of alkane = 100cm3
Volume of oxygen = 650cm3
Alkane = Cn H (2n+n)
Cn H (2n+n)+(3 n+12 )O
2
→ nCO2+(n+1) H 2O
From the gas law formula, ratio of
n( O2
alkane )=V ( O2
alkane )¿ 650 cm3
100 cm3
¿ 132
n¿¿
3 n+1=13
3 n=12
n=4
Cn H ( 2 n+n )+( 3n+12 )O
2
→ nCO2+(n+1 ) H 2O
NORHAZRIMELIANA BINTI ABDUL RAHIM 781117065006001
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HBSC3203_V2 CHEMISTRY II / KIMIA II
C4 H 10+( 132 )O
2
→ 4 CO2+5 H 2O
Isomer of X is C4 H 10
(b)
Cyclohexadiene : C6 H 8
1,3- Cyclohexadiene
CH
CH CH
CH2 CH
CH2
1,4- Cyclohexadiene
CH2
CH CH
CH CH
CH2
NORHAZRIMELIANA BINTI ABDUL RAHIM 781117065006001
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HBSC3203_V2 CHEMISTRY II / KIMIA II
2-ethylcyclohexa-1,3-dien : C8 H 12
CH3
CH2
C
CH CH
CH CH2
CH2
(c)
Initiation step:
Propagation step:
Termination step:
NORHAZRIMELIANA BINTI ABDUL RAHIM 781117065006001
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HBSC3203_V2 CHEMISTRY II / KIMIA II
(d)
Three industrial important of cyclopentane:
i. Cyclopentane as a blowing agent in the manufacture of polyurethane insulating foam, as found in
many domestic appliances such as refrigerators and freezers, in replacing environmentally
damaging alternatives. There have many advantages such as little loss of cyclopentane during
foaming, low thermal conductivity of foam, low diffusion rate out of foam and good availability.
ii. Cyclopentane is also used in manufacture of resin, adhesives, pharma intermediate and as a
gasoline additive as octane booster
iii. Cyclopentane being halogen free compound is environment friendly with Zero-Ozone Depletion
Potential and thus is fast replacing Chloro Fluoro Carbon (CFC) applications in refrigerator and
thermal insulation.
NORHAZRIMELIANA BINTI ABDUL RAHIM 781117065006001
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HBSC3203_V2 CHEMISTRY II / KIMIA II
REFERENCES
Bartholomew, C. H., & Farrauto, R. J. (2011). Fundamentals of industrial catalytic processes.
John Wiley & Sons.
Egolf, L. M., Wessel, M. D., & Jurs, P. C. (1994). Prediction of boiling points and critical
temperatures of industrially important organic compounds from molecular structure. Journal of
Chemical Information and Computer Sciences,34(4), 947-956.
http://www.chemicalland21.com/specialtychem/finechem/cyclopentanone.htm
http://www.nuffieldfoundation.org/practical-chemistry/catalysis-reaction-between-sodium-
thiosulfate-solution-and-ironiii-nitrate-solut
http://www.researchgate.net/publication/
241923746_Surface_studies_of_nickel._Cyclohexene_13-cylohexadiene_14-
cyclohexadiene_trimethyphosphine
http://www.vurup.sk/sites/vurup.sk/archivedsite/www.vurup.sk/pc/vol47_2005/issue3/pdf/
PC_3_2005_Sadeghzadeh_final.pdf
NORHAZRIMELIANA BINTI ABDUL RAHIM 781117065006001
