UNIVERSITY EXAMINATIONS
OCTOBER/NOVEMBER 2025
ACH3701
Applied Chemical Principles
100 Marks
Duration 3.0 Hours
EXAMINERS
First Examiner: Prof TE Motaung
Second Examiner: Dr N. Dladla
External Examiner: Prof C Zvinowanda
Instructions:
Closed book examination
Answer ANY FOUR questions.
Each question counts 25 Marks.
Connectivity to the internet and the IRIS invigilation system is compulsory.
The use of non-programmable pocket calculator is permissible
This paper consists of 9 pages.
Supplementary information/data as APPENDIX A are on pages 6 and 7.
The instructions for the uploading of the examination paper can be found in
APPENDIX B on pages 8 and 9.
Tick the honour pledge box before submission, if it appears on the screen.
QUESTION 1 [25]
, ACH3701
OCTOBER/NOVEMBER 2025
1.1 Give 3 types of fuels and explain each. (6)
1.2 Mention 5 fuel sources and give an example of an industries that consume the
technology in South Africa respectively. (5)
1.3 Define the law of conservation of energy and give two examples. (4)
1.4 Define Heat in thermodynamics illustrating with two examples. (5)
1.5 Mention and explain 5 ways in which energy is presented in nature. (5)
QUESTION 2 [25]
2.1 With an aid of a diagram, describe how a nuclear reactor works. (6)
2.2 Give 3 differences between a boiling water nuclear reactor and a pressurized
nuclear water reactor. (6)
2.3 Draw a diagram of a turbine generator and explain the functions of all its parts. (7)
2.4 Give an ideal principle of predicting performance of a fuel cell and illustrate the
principle with an aid of a calculation. (6)
QUESTION 3 [25]
3.1 Estimate the solubility of calcium iodide (Pbl2) at 25 oC in the presence of 0.10 M
NaI (aq).
(6)
3.2 Will BaSO4 precipitate from a solution containing 2.5 x10 -4 M Ba+2,(barium ion), if
enough soluble salt, Na2SO4, is added to make the solution 4.5 x10-4 M in SO42-
? (6)
, ACH3701
OCTOBER/NOVEMBER 2025
3.3 The solubility product of calcium fluoride (CaF2) is 3.45×10−11. If 1.5 mL of a 0.10
M solution of NaF is added to 130 mL of a 1.0×10 −5 M solution of Ca(NO3)2, will
CaF2 precipitate? (6)
3.3 Briefly describe the proximate analysis of coal. (4)
3.5 Describe a typical oxidation reaction, illustrating it by rusting of iron as an
example. (5)
QUESTION 4 [25]
4.1 Describe the formation of a charcoal. Motivate your answer with chemical
reactions. (4)
4.2 Give 7 types of biomass thermochemical conversion technologies and explain the
differences amongst them as well as examples where possible. (7)
4.2 List three possible disadvantages when a car owner replaces the manufacturer’s
recommended gasoline with methanol. (3)
4.3 Label and explain in details the following diagram, motivate your answers with
chemical equations. Give half cells and the net if necessary (7)
4.3.1 Give three fundamental functions of E in the above diagram. (3)
, ACH3701
OCTOBER/NOVEMBER 2025
QUESTION 5
[25]
5.1 Provide a detailed mechanism for the polymerization of styrene on treatment with
BF3 in the presence of trace amounts of water.
(6)
5.2 Calculate the average molecular weight for a polymer sample which consist of 12
moles of polymer molecules having molecular weight of 48,000 g/mol and 16
moles of polymer molecules having molecular weight of 36,000 g/mol.
(3)
5.3 Describe the functionality of a lead storage cell. Use chemical equations and
diagrams to illustrate your answer, where appropriate.
(10)
5.4 List six conditions of safety measures when disinfecting water using hose hold
bleach such as 6 or 8.25% of sodium hypochlorite (6)
--------------------------------------The end------------------------------------------------
APPENDIX A: SUPPLEMENTARY INFORMATION / DATA
Potential Health Effects
1
MCL or Sources of
MCLG from Long-Term Exposure
Contaminant TT1 Contaminant in
(mg/L)2 Above the MCL (unless
(mg/L)2 Drinking Water
specified as short-term)
Bromate zero 0.010 Increased risk of cancer Byproduct of
drinking water
disinfection
OCTOBER/NOVEMBER 2025
ACH3701
Applied Chemical Principles
100 Marks
Duration 3.0 Hours
EXAMINERS
First Examiner: Prof TE Motaung
Second Examiner: Dr N. Dladla
External Examiner: Prof C Zvinowanda
Instructions:
Closed book examination
Answer ANY FOUR questions.
Each question counts 25 Marks.
Connectivity to the internet and the IRIS invigilation system is compulsory.
The use of non-programmable pocket calculator is permissible
This paper consists of 9 pages.
Supplementary information/data as APPENDIX A are on pages 6 and 7.
The instructions for the uploading of the examination paper can be found in
APPENDIX B on pages 8 and 9.
Tick the honour pledge box before submission, if it appears on the screen.
QUESTION 1 [25]
, ACH3701
OCTOBER/NOVEMBER 2025
1.1 Give 3 types of fuels and explain each. (6)
1.2 Mention 5 fuel sources and give an example of an industries that consume the
technology in South Africa respectively. (5)
1.3 Define the law of conservation of energy and give two examples. (4)
1.4 Define Heat in thermodynamics illustrating with two examples. (5)
1.5 Mention and explain 5 ways in which energy is presented in nature. (5)
QUESTION 2 [25]
2.1 With an aid of a diagram, describe how a nuclear reactor works. (6)
2.2 Give 3 differences between a boiling water nuclear reactor and a pressurized
nuclear water reactor. (6)
2.3 Draw a diagram of a turbine generator and explain the functions of all its parts. (7)
2.4 Give an ideal principle of predicting performance of a fuel cell and illustrate the
principle with an aid of a calculation. (6)
QUESTION 3 [25]
3.1 Estimate the solubility of calcium iodide (Pbl2) at 25 oC in the presence of 0.10 M
NaI (aq).
(6)
3.2 Will BaSO4 precipitate from a solution containing 2.5 x10 -4 M Ba+2,(barium ion), if
enough soluble salt, Na2SO4, is added to make the solution 4.5 x10-4 M in SO42-
? (6)
, ACH3701
OCTOBER/NOVEMBER 2025
3.3 The solubility product of calcium fluoride (CaF2) is 3.45×10−11. If 1.5 mL of a 0.10
M solution of NaF is added to 130 mL of a 1.0×10 −5 M solution of Ca(NO3)2, will
CaF2 precipitate? (6)
3.3 Briefly describe the proximate analysis of coal. (4)
3.5 Describe a typical oxidation reaction, illustrating it by rusting of iron as an
example. (5)
QUESTION 4 [25]
4.1 Describe the formation of a charcoal. Motivate your answer with chemical
reactions. (4)
4.2 Give 7 types of biomass thermochemical conversion technologies and explain the
differences amongst them as well as examples where possible. (7)
4.2 List three possible disadvantages when a car owner replaces the manufacturer’s
recommended gasoline with methanol. (3)
4.3 Label and explain in details the following diagram, motivate your answers with
chemical equations. Give half cells and the net if necessary (7)
4.3.1 Give three fundamental functions of E in the above diagram. (3)
, ACH3701
OCTOBER/NOVEMBER 2025
QUESTION 5
[25]
5.1 Provide a detailed mechanism for the polymerization of styrene on treatment with
BF3 in the presence of trace amounts of water.
(6)
5.2 Calculate the average molecular weight for a polymer sample which consist of 12
moles of polymer molecules having molecular weight of 48,000 g/mol and 16
moles of polymer molecules having molecular weight of 36,000 g/mol.
(3)
5.3 Describe the functionality of a lead storage cell. Use chemical equations and
diagrams to illustrate your answer, where appropriate.
(10)
5.4 List six conditions of safety measures when disinfecting water using hose hold
bleach such as 6 or 8.25% of sodium hypochlorite (6)
--------------------------------------The end------------------------------------------------
APPENDIX A: SUPPLEMENTARY INFORMATION / DATA
Potential Health Effects
1
MCL or Sources of
MCLG from Long-Term Exposure
Contaminant TT1 Contaminant in
(mg/L)2 Above the MCL (unless
(mg/L)2 Drinking Water
specified as short-term)
Bromate zero 0.010 Increased risk of cancer Byproduct of
drinking water
disinfection
