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)
2003 - Q4
In which layer of the atmosphere does ozone act as a UV radiation shield?
(A) Mesosphere
(B) Stratosphere
(C) Thermosphere
(D) Troposphere
2003 - Q9
What is the name of the compound shown?
(A) 1-chloro-1,2-difluoropropane
(B) 3-chloro-2,3-difluoropropane
(C) 1,2-difluoro-1-chloropropane
(D) 1-chloro-1,2-difluoropentane
2003 - Q10
The graph shows October ozone concentrations above Halley Bay in Antarctica between 1956 and 1998.
Based on these data alone, which of the following is a valid statement about the concentration of ozone above Halley Bay?
(A) It was greater in 1998 than in 1993.
(B) It will be greater in 2004 than in 1998.
(C) The variation in ozone concentration between 1960 and 1970 was due to changes in atmospheric CFC concentrations.
(D) The variation in ozone concentration from one year to the next is due only to changes in atmospheric CFC concentrations.
2003 - Q12
The graph shows the mass and amount of carbon, fluorine and chlorine atoms in one mole of a compound.
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What is the molecular formula for this compound?
(A) CF2Cl
(B) CF2Cl2
(C) C2F3Cl3
(D) C2F4Cl2
2004 - Q4
Which term describes the relationship between the compounds shown below?
(A) Allotropes
(B) Isomers
(C) Isotopes
(D) Monomers
2004 - Q6
Which of the following is the Lewis electron dot formula for ozone?
2004 - Q8
Which of the following graphs illustrates the layered structure of the atmosphere?
2004 - Q12
Two of the compounds shown below react together to form a new compound with a coordinate covalent bond.
Which of the following compounds react this way?
(A) Methane and ammonia
(B) Methane and water
(C) Hydrogen fluoride and ammonia
(D) Hydrogen fluoride and methane
2001 - Q27 (4 marks)
Oxygen exists in the atmosphere as the allotropes oxygen and ozone. The graph shows a typical change in ozone concentration with changing altitude.
Compare the environmental effects of the presence of ozone in the upper and lower atmosphere.
2002 - Q25 (6 marks)
(a) What is the systematic name of the CFC in the diagram? (1 mark)
(b) Identify the bonding within ozone, using a Lewis electron-dot diagram. (2 marks)
(c) Discuss how CFCs damage the ozone layer, using relevant equations. (3 marks)
2004 - Q27 (7 marks)
The table shows ozone depletion potential (ODP) for different compounds.
Discuss the problems associated with the use of CFCs, and assess the suitability of alternative chemicals as replacements, using data in the table.
2006 - Q28 (4 marks)
The diagram shows recent atmospheric ozone concentrations above Antarctica.
Explain how this information was obtained, and outline the changes that have occurred in atmospheric ozone concentrations above Antarctica during the past twenty years.
2007 - Q16 (5 marks)
The diagram represents a section of the layered structure of Earth's atmosphere.
(a) Identify the layers of the atmosphere labelled X and Y. (1 mark)
(b) Ozone is a gas found in layers X and Y.
Explain the effect of ozone in each of these layers (4 marks)
2008 - Q18 (5 marks)
(a) Draw Lewis electron dot structures for oxygen and ozone. (2 marks)
(b) Account for the differences in the properties of oxygen and ozone on the basis of their molecular structure and bonding. (3 marks)
2011 - Q22 (4 marks)
(a) Use chemical equations to show how ozone is depleted in the stratosphere. (2 marks)
(b) Outline ONE method used to monitor stratospheric ozone. (2 marks)
2012 - Q29 (5 marks)
Draw a labelled diagram to show the layered structure of the atmosphere. In your diagram include:
• the names of TWO atmospheric pollutants, positioned in the layers where the detrimental impact occurs
• the names of the sources of the two pollutants identified.
2013 - Q30 (6 marks)
The images below represent the concentration of ozone in the atmosphere above Antarctica near the South Pole for the years 1979, 1994 and 2012, measured at the same time each year.
Account for the changes in ozone concentration above Antarctica between 1979 and 2012. Your response should include relevant equations.
2015 - Q22 (7 marks)
The table shows data for ozone concentrations over 50 years in the upper atmosphere above Antarctica.
Year Ozone Concentration (Dobson Units)
1955 320
1960 300
1970 300
1980 260
1995 130
2000 130
2005 150
(a) Draw a line graph of the data on the grid provided. (4 marks)
(b) Describe a method by which this data could have been measured. (3 marks)
2016 - Q30 (7 marks)
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The use of CFCs has caused ozone depletion in the stratosphere.
Explain the steps that have been taken to reduce this problem. Include relevant chemical equations in your answer.
2005 - Q13
What is the name of the following compound?
(A) 1,2-difluoro-1-chloroethane
(B) 1,2-difluoro-2-chloroethane
(C) 1-chloro-1,2-difluoroethane
(D) 2-chloro-1,2-difluoroethane
2006 - Q5
How many isomers are there for C3H6Cl2?
(A) 3
(B) 4
(C) 5
(D) 6
2007 - Q15
The following equations show the overall effect of the presence of chlorine free radicals (•Cl) on ozone in the stratosphere.
•Cl+ O3→ •ClO + O2
•ClO + •O→ •Cl+O2
Which term best describes the role of the chlorine free radical in this process?
(A) Anion
(B) Catalyst
(C) Initiator
(D) Oxidant
2008 - Q3
Which term describes the relationship between oxygen and ozone?
(A) Allotropes
(B) Conjugates
(C) Isomers
(D) Isotopes
2008 - Q4
What is the main constituent of the atmosphere at ground level?
(A) Water
(B) Oxygen
(C) Nitrogen
(D) Carbon dioxide
2009 - Q12
What is the IUPAC name of the following compound?
(A) 3,4–dichloro–2–fluorohexane
(B) 3,4–dichloro–5–fluorohexane
(C) 2–fluoro–3,4–dichlorohexane
(D) 5–fluoro–3,4–dichlorohexane
2010 - Q4
The diagram shows the structural formula of a gas.
How many isomers does this compound have?
(A) 1
(B) 2
(C) 3
(D) 4
2010 - Q16
Which of the following Lewis structures does NOT contain a coordinate covalent bond?
2011 - Q4
Which of the following gases can cause major depletion of the ozone layer?
(A) O2
(B) NO2
(C) CO2
(D) CCl3F
2011 - Q9
What property of O3 makes it more soluble in water than O2 in water?
(A) O3 is a polar molecule.
(B) O3 has a resonance structure.
(C) O3 is a highly reactive molecule.
(D) O3 has a coordinate covalent bond.
2011 - Q14
How many isomers are there for C3H6BrCl?
(A) 3
(B) 4
(C) 5
(D) 6
2012 - Q9
Which of the following contains a coordinate covalent bond?
(A) NH3
(B) NH4 +
(C) H2O
(D) OH–
2012 - Q12
What is the correct IUPAC name for the following compound?
(A) 2-chloro-2-fluorobutane
(B) 2-fluoro-3-chlorobutane
(C) 3-fluoro-2-chlorobutane
(D) 3-chloro-2-fluorobutane
2013 - Q3
What is the main environmental problem associated with chlorofluorocarbon compounds?
(A) Acid rain
(B) Eutrophication
(C) Global warming
(D) Ozone depletion
2013 - Q16
Which two species will react to form a product containing a coordinate covalent bond?
(A) Ca(s) and 2H+ (aq)
(B) H2O(l) and H+ (aq)
(C) Ag+ (aq) and Cl– (aq)
(D) NH4+ (aq) and OH– (aq)
2013 - Q20
The structures of ozone and molecular oxygen are shown.
Ozone is more easily decomposed than molecular oxygen because
(A) it is polar.
(B) it is a bent molecule.
(C) it has a greater molecular mass.
(D) it has a lower average bond energy.
2014 - Q1
In which layer of the atmosphere is ozone considered a pollutant?
(A) Mesosphere
(B) Stratosphere
(C) Thermosphere
(D) Troposphere
2014 - Q2
What is the IUPAC name of the following compound?
(A) 1,2-dibromo-2-fluoropropane
(B) 2,3-dibromo-2-fluoropropane
(C) 2-fluoro-2,3-dibromopropane
(D) 2-fluoro-1,2-dibromopropane
2014 - Q9
Four compounds, W, X, Y and Z, are represented below.
Which of the following is a pair of isomers?
(A) W and X
(B) W and Y
(C) X and Y
(D) Y and Z
2014 - Q11
Which of the following does NOT represent the formation of a coordinate covalent bond?
2015 - Q1
In which layer of the atmosphere does ozone absorb the most UV radiation?
(A) Mesosphere
(B) Stratosphere
(C) Thermosphere
(D) Troposphere
2015 - Q6
Which of the following is the most suitable replacement for CFCs in terms of reducing their environmental impact?
(A) CH4
(B) CH2F2
(C) CH2ClF
(D) CHCl2CCl2F
2016 - Q11
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What is the IUPAC name of the following compound?
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(A) 1-bromo-1-chloro-2,2,2-trifluoroethane
(B) 1-chloro-1-bromo-2,2,2-trifluoroethane
(C) 2-chloro-2-bromo-1,1,1-trifluoroethane
(D) 2-bromo-2-chloro-1,1,1-trifluoroethane
2017 - Q3
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What is the name of this compound?
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(A) 2-chloro-1-fluorobutane
(B) 3-chloro-4-fluorobutane
(C) 1-fluoro-2-chlorobutane
(D) 4-fluoro-3-chlorobutane
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