Barker College Chemistry Department
Past HSC Chemistry Questions
Please click the following link for the past papers of the new syllabus: HOME | Past Hsc Chem3 (andrewchoi2.wixsite.com)
2002 - Q1
Which condition would be best for the fermentation of sugars by yeast?
(A) Low oxygen concentration and a temperature between 25'C and 35'C
(B) High oxygen concentration and a temperature between 25'C and 35'C
(C) Low oxygen concentration and a temperature between 45'C and 60'C
(D) High oxygen concentration and a temperature between 45'C and 60'C
2002 - Q2
What is the catalyst for the conversion of ethanol to ethene?
(A) NaOH
(B) H2SO4
(C) HNO3
(D) Pt
2003 - Q6
The table gives the heat of combustion in kJ/g for a number of different fuels.
Fuel Heat of combustion (kJ/ g)
Methanol 22.7
Ethanol 29.6
Propanol 33.6
Petrol (octane) 47.8
The heat of combustion in kJ/ mol for one of the fuels was calculated as 2016 kJ/ mol.
What was the fuel?
(A) Methanol
(B) Ethanol
(C) Propanol
(D) Petrol
2001 - Q17 (6 marks)
Students were asked to perform a first-hand investigation to determine the molar heat of combustion of ethanol.
The following extract is from the practical report of one student.
Lab data:
Mass of water = 250.0 g
Initial mass of burner = 221.4 g
Final mass of burner = 219.1 g
Initial temperature of water = 19.0'C
Final temperature of water = 59'C
(a) After completing the calculations correctly, the student found that the answer did not agree with the value found in data books. Suggest ONE reason for this. (1 mark)
(b) Propose TWO adjustments that could be made to the apparatus or experimental method to improve the accuracy of results (2 marks)
(c) Calculate the molar heat of combustion of ethanol, using the student's data. (3 marks)
2004 - Q13
A student used the apparatus below to determine the molar heat of combustion of propanol.
The following results were obtained:
Mass of 1-propanol burnt = 0.60 g
Mass of water heated = 200 g
Initial temperature of water = 21.0°C
The molar heat of combustion of 1-propanol is 2021 kJ mol−1 . Assuming no heat loss, what would be the final temperature of the water?
(A) 24.2°C
(B) 29.1°C
(C) 45.2°C
(D) 48.4°C
2005 - Q3
The heat of combustion of butan-1-ol is 2676 kJ mol −1.
What is the value of the heat of combustion in kJ g−1 ?
(A) 30.41
(B) 36.10
(C) 44.60
(D) 47.79
2006 - Q2
Catalysts are required for the production of both ethanol from ethylene and ethylene from ethanol.
2003 - Q16 (3 marks)
You performed a first-hand investigation that monitored mass changes during the fermentation of glucose to ethanol.
(a) Outline the procedure you used. (2 marks)
(b) Write a balanced chemical equation for this reaction (1 mark)
2003 - Q22 (3 marks)
(a) Write a balanced chemical equation for the complete combustion of ethanol. (1 mark)
(b) A mass of 72.5 g of ethanol was burnt completely in air. Calculate the volume of carbon dioxide that was produced at 25°C and 100 kPa. (2 marks)
2004 - Q25 (5 marks)
The table shows properties of some fuels.
Assess the potential of ethanol as an alternative fuel, making use of data from the table.
2005 - Q17 (3 marks)
The heat of combustion of ethanol is 1367 kJ mol–1. In a first-hand investigation to determine the heat of combustion of ethanol, the experimental value determined differed from the theoretical value.
(a) Identify a reason for this difference. (1 mark)
(b) Calculate the theoretical mass of ethanol required to heat 200 mL of water from 21.0°C to 45.0°C. (2 marks)
2006 - Q4
A student used the apparatus shown to determine the molar heat of combustion of ethanol.
The following results were obtained.
Initial mass of burner 133.20 g
Final mass of burner 132.05 g
Initial temperature of water 25.0°C
Final temperature of water 45.5°C
What is the molar heat of combustion calculated from this data?
(A) 22.4 kJ mol–1
(B) 25.7 kJ mol–1
(C) 1030 kJ mol–1
(D) 1180 kJ mol–1
2007 - Q4
What is the IUPAC name for the following compound?
(A) Hexan-3-ol
(B) Hexan-4-ol
(C) Heptan-3-ol
(D) Heptan-5-ol
2006 - Q18 (4 marks)
A student studying the mass change that occurs during fermentation added glucose, water and yeast to a flask and stoppered the flask with some cotton wool.
The student measured the mass of the flask daily for seven days. The table shows the data collected.
Day Mass (g)
1 381.05
2 376.96
3 373.42
4 370.44
5 370.42
6 370.40
7 370.39
(a) Calculate the moles of CO2 released between days 1 and 7. (1 mark)
(b) Calculate the mass of glucose that underwent fermentation between days 1 and 7. Include a balanced chemical equation in your answer. (3 marks)
2007 - Q24 (5 marks)
The heats of combustion (–ΔHc ) of three alkanols were determined.
The results are shown in the table.
Alkanol Heat of combustion (kJ mol–1)
methanol 480
ethanol 920
butan-1-ol 1800
(a) Plot a graph of the heat of combustion versus the molecular weight for the three alkanols. (3 marks)
(b) (i) Use the graph to estimate the heat of combustion of propan-1-ol. (1 mark)
(ii) The theoretical value for the heat of combustion of propan-1-ol is more than 2000 kJ mol–1.
Suggest a chemical reason, other than heat loss, for the difference between this value and the estimated value from part (b) (i). (1 mark)
2008 - Q22 (5 marks)
The following extract was taken from the website of a leading car manufacturer.
Awaiting copyright
Critically evaluate the extract with reference to ethanol being a ‘carbon-neutral’ fuel. Support your answer with relevant chemical equations.
2008 - Q24 (5 marks)
The table shows four fuels and their various properties.
2008 - Q5
Why is ethanol used in preference to water as the main ingredient of perfume?
(A) Ethanol is cheaper to produce.
(B) Ethanol has no detectable odour.
(C) Ethanol dissolves esters more readily.
(D) Ethanol has a significantly lower density.
2008 - Q6
What is the specific heat of a compound?
(A) The quantity of heat required to boil 1 g of the compound
(B) The quantity of heat required to melt 1 g of the compound
(C) The quantity of heat required to increase the temperature of the compound by 1°C
(D) The quantity of heat required to increase the temperature of 1 g of the compound by 1°C
2008 - Q10
The molar heat of combustion of ethanol is 1367 kJ mol–1.
What quantity of ethanol must be combusted to raise the temperature of 1.0 kg water from 50°C to boiling point at sea level (assuming no loss of heat to the surroundings)?
(A) 6.5 g
(B) 7.0 g
(C) 209 g
(D) 300 g
2009 - Q5
The apparatus shown is used in a first-hand investigation to determine and compare the heat of combustion of three different liquid alkanols.
Which is the independent variable?
(A) Type of alkanol used
(B) Amount of water used
(C) Amount of alkanol used
(D) Temperature change in the water
2009 - Q13
In a fermentation experiment 6.50 g of glucose was completely converted to ethanol and carbon dioxide.
What is the mass of carbon dioxide produced?
(A) 1.59 g
(B) 3.18 g
(C) 9.53 g
(D) 13.0 g
(a) Which fuel provides the greatest amount of energy per gram? (1 mark)
(b) A car has an 80 L petrol tank. Calculate the energy released by the complete combustion of one full tank of petrol. (2 marks)
(c) How many litres of hydrogen gas at 25°C and 100 kPa would be needed to supply the same amount of energy as 80 L of petrol? (2 marks)
2009 - Q17 (4 marks)
Water and ethanol are both used as solvents. Explain the differences and similarities in their solvent behaviour in terms of their molecular structures. Include a diagram in your answer.
2009 - Q20 (4 marks)
(a) Calculate the mass of ethanol that must be burnt to increase the temperature of 210 g of water by 65°C, if exactly half of the heat released by this combustion is lost to the surroundings.
The heat of combustion of ethanol is 1367 kJ mol −1 . (3 marks)
(b) What are TWO ways to limit heat loss from the apparatus when performing a first-hand investigation to determine and compare heat of combustion of different liquid alkanols? (1 mark)
2010 - Q23 (3 marks)
(a) Write a balanced chemical equation for the complete combustion of 1-butanol. (1 mark)
(b) A student measured the heat of combustion of three different fuels. The results are shown in the table.
Fuel Heat of combustion (kJ g−1 )
A −48
B −38
C −28
The published value for the heat of combustion of 1-butanol is 2676 kJ mol−1.
Which fuel from the table is likely to be 1-butanol? Justify your answer. (2 marks)
2011 - Q21 (4 marks)
What features of the molecular structure of ethanol account for its extensive use as a solvent? Include a diagram in your answer.
2012 - Q26 (8 marks)
(a) Construct separate flow diagrams for the production of ethanol from each raw material. (5 marks)
petroleum sugar cane
(b) Compare the environmental sustainability of producing ethanol from these two raw materials. (3 marks)
2012 - Q31 (5 marks)
The boiling points of some alkanols are given in the table.
Alkanol Boiling point (°C)
Methanol 65
Ethanol 79
Propan-1-ol 97
Pentan-1-ol 138
Hexan-1-ol 157
Heptan-1-ol 176
(a) Using the data provided, construct a graph that shows the relationship between carbon chain length and boiling point. (3 marks)
(b) Using the graph, predict the boiling point of butan-1-ol. (1 mark)
(c) What is the intermolecular force responsible for the trend shown in the graph?
2010 - Q15
What mass of ethanol is obtained when 5.68 g of carbon dioxide is produced during fermentation, at 25°C and 100 kPa?
(A) 2.95 g
(B) 5.95 g
(C) 33.6 g
(D) 147.2 g
2010 - Q17
A student completed an experiment to determine the amount of energy absorbed by a volume of water.
The following data were recorded.
Mass of beaker 215.6 g
Mass of beaker plus water 336.1 g
Final temperature of water 71.0°C
Energy absorbed 21.2 kJ
What was the initial temperature of the water?
(A) 15°C
(B) 25°C
(C) 29°C
(D) 42°C
2011 - Q1
Which of the following industrial processes is used to produce ethanol from ethylene?
(A) Hydration
(B) Dehydration
(C) Addition polymerisation
(D) Condensation polymerisation
2011 - Q2
Which of the following shows two products that result from the fermentation of glucose?
(A) Cellulose and water
(B) Ethanol and oxygen
(C) Carbon dioxide and water
(D) Ethanol and carbon dioxide
2011 - Q6
Which property would be most useful in distinguishing between butan-1- ol and propan-1-ol?
(A) Boiling point
(B) Colour
(C) Conductivity
(D) Density
2011 - Q17
The molar heat of combustion of pentan-1-ol is 2800 kJ mol−1 . A quantity of pentan-1-ol was combusted, generating 108 kJ of heat.
What mass of pentan-1-ol was combusted?
(A) 2.29 g
(B) 2.86 g
(C) 3.32 g
(D) 3.40 g
2012 - Q5
Which of the following is a balanced equation representing the fermentation of glucose?
2012 - Q17
The heat of combustion of propan-1-ol is 2021 kJ mol–1. Combustion takes place according to the equation:
2C3H7OH(l) + 9O2(g) → 6CO2(g) + 8H2O(l)
What mass of water is formed when 1530 kJ of energy is released?
(A) 3.4 g
(B) 14 g
(C) 55 g
(D) 144 g
2013 - Q27 (4 marks)
A 0.259 g sample of ethanol is burnt to raise the temperature of 120 g of an oily liquid, as shown in the graph. There is no loss of heat to the surroundings.
Using the information shown on the graph, calculate the specific heat capacity of the oily liquid. The heat of combustion of ethanol is 1367 kJ mol–1 .
2014 - Q22 (6 marks)
A student performed a first-hand investigation to determine the quantitative relationship between heat of combustion and molar mass of alkanols. The student did this by burning different alkanols to heat water as shown in the diagram below. The calculated heats of combustion for four of the alkanols are given in the table.
(a) On the grid below, graph both the calculated and the theoretical heat of combustion against the molar mass of the alkanols. (3 marks)
(b) Discuss the validity of the student’s investigation. (3 marks)
2014 - Q31 (7 marks)
With reference to the underlying chemistry and with relevant equations, assess the impacts on society of TWO uses of ethanol.
2016 - Q23 (6 marks)
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A spirit burner containing ethanol was used to heat water in a conical flask for three minutes to measure the molar heat of combustion of ethanol.
The results from the investigation are shown.
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(a) On the grid, draw a line graph to represent the data contained in the table. (3 marks)
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(b) The following values were also recorded during the investigation:
Initial mass of spirit burner = 236.14 g
Final mass of spirit burner = 235.56 g
Calculated experimental molar heat of combustion of ethanol = –827 kJ mol–1.
Using information from the previous page and the above values, determine the mass of water that was in the conical flask. (3 marks)
2013 - Q4
Butan-1-ol burns in oxygen according to the following equation.
C4H9OH(l) + 6O2(g) → 4CO2(g) + 5H2O(l)
How many moles of carbon dioxide would form if two moles of butan-1-ol were burnt in excess oxygen?
(A) 2
(B) 4
(C) 8
(D) 10
2013 - Q11
The table shows the heat of combustion for four compounds.
Compound Heat of combustion (kJ mol–1 )
CO 233
CH4 890
C2H2 1300
C2H6 1560
Which of these compounds would produce the greatest amount of energy if 1.00 g of each is burnt?
(A) CO
(B) CH4
(C) C2H2
(D) C2H6
2016 - Q25 (4marks)
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An unattended car is stationary with its engine running in a closed workshop. The workshop is 5.0 m × 5.0 m × 4.0 m and its volume is 1.0 × 10 ^5 L. The engine of the car is producing carbon monoxide in an incomplete combustion according to the following chemical equation:
C8H18(l) + 17/2 O2 (g) ---> 8CO2(g) + 9H2O(l)
Exposure to carbon monoxide at levels greater than 0.100 g L–1 of air can be dangerous to human health.
6.0 kg of octane was combusted by the car in this workshop.
Using the equation provided, determine if the level of carbon monoxide produce in the workshop would be dangerous to human health. Support your answer wit relevant calculations.
2014 - Q19
An experimental car using ethanol as a fuel source requires 2270 kJ of energy for every kilometre travelled.
Given that the heat of combustion of ethanol is 1360 kJ mol−1 , what is the maximum distance that the car can travel on 1.0 kilogram of ethanol?
(A) 1.7 km
(B) 13 km
(C) 28 km
(D) 36 km
2015 - Q8
Which of the following statements best explains the solubility of ethanol in octane?
(A) Ethanol and octane are both non‑polar.
(B) Ethanol forms hydrogen bonds with octane.
(C) Ethanol forms dispersion forces with octane.
(D) Ethanol forms dipole‑dipole bonds with octane.
2015 - Q17
What volume of carbon dioxide will be produced if 10.3 g of glucose is fermented at 25°C and 100 kPa?
(A) 1.30 L
(B) 1.42 L
(C) 2.57 L
(D) 2.83 L
2015 - Q20
The table shows the heat of combustion of four straight chain alkanols.
Number of C atoms in Heat of combustion (kJ mol–1)
straight chain alkanol
1 726
3 2021
5 3331
7 4638
What is the mass of water that could be heated from 20°C to 45°C by the complete combustion of 1.0 g of heptan-1-ol?
(A) 0.032 kg
(B) 0.044 kg
(C) 0.36 kg
(D) 0.38 kg
2016 - Q5
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Which of the following diagrams best represents the bonding between molecules of water and ethanol?
2017 - Q9
The following equipment was set up to measure the heat of combustion of an alkanol.
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Black deposits were observed on the bottom of the conical flask and the heat of combustion measured was lower than the theoretical value.
Which of the following equations could account for these observations?
