Component

Component: Chemical Monitoring and Management

Question 11

Written Paper Section I Question 11 - 2002 HSC

Substance emitted in a higher level by a car engine burning fuel with insufficient air compared with an engine with a correct fuel to air ratio

Question 11

Written Paper Section I Question 11 - 2001 HSC

Reason why chlorine is used to treat local water supplies

Question 12

Written Paper Section I Question 12 - 2002 HSC

Most effective method for removing oxides of nitrogen produced by the combustion of coal

Question 12

Written Paper Section I Question 12 - 2001 HSC

Purpose of the atomic absorption spectrophotometer

Question 13

Written Paper Section I Question 13 - 2002 HSC

Major advantage of the development early in the 20th century of the Haber Process for producing ammonia

Question 13

Written Paper Section I Question 13 - 2001 HSC

Likely reason for variation in results of a chemical analysis of a sample of fertiliser

Question 14

Written Paper Section I Question 14 - 2002 HSC

Given a standard graph and an equation for the chemical process, select a graph correctly comparing the yield of ammonia at two different temperatures.

Question 14

Written Paper Section I Question 14 - 2001 HSC

Most effective design for a microscopic membrane filter to purify contaminated water

Question 15

Written Paper Section I Question 15 - 2002 HSC

Given a table of results of chemical tests for some cations and anions, select a conclusion consistent with a table of results when an unknown solution was tested.

Question 15

Written Paper Section I Question 15 - 2001 HSC

Identification of results consistent with the presence of a cation in a solution

Student Responses (15)

Band 5/6 response 1 Band 5/6 response 2 Band 5/6 response 3 Band 4/5 response 1 Band 4/5 response 2 Band 4/5 response 3 Band 3/4 response 1 Band 3/4 response 2 Band 3/4 response 3 Band 2/3 response 1 Band 2/3 response 2 Band 2/3 response 3 Band 1/2 response 1 Band 1/2 response 2 Band 1/2 response 3

Question 22-24

Written Paper Section I Question 22-24 - 2001 HSC

22. Justify the procedure used to prepare an ester in a school laboratory and include relevant chemical equations. 23(a) State Brönsted-Lowry's definition of a base. (b) Calculate the molar mass of a base in a household cleaning agent. 24(a) State a use of ammonia other than as a cleaning agent. (b) State the effect on the yield of the Haber Process when ammonia is liquefied. (c) Explain why it is essential to monitor temperature and pressure inside the reaction vessel when producing ammonia.

Student Responses (16)

Exemplary response 1 Band 5/6 response 1 Band 5/6 response 2 Band 5/6 response 3 Band 4/5 response 1 Band 4/5 response 2 Band 4/5 response 3 Band 3/4 response 1 Band 3/4 response 2 Band 3/4 response 3 Band 2/3 response 1 Band 2/3 response 2 Band 2/3 response 3 Band 1/2 response 1 Band 1/2 response 2 Band 1/2 response 3

Question 24

Written Paper Section I Question 24 - 2002 HSC

Assess the impact of atomic absorption spectroscopy (AAS) on the scientific understanding of trace elements.

Student Responses (14)

Question 25

Written Paper Section I Question 25 - 2010 HSC

Describe the relationship between dissolved oxygen and biochemical oxygen demand. Explain why it is important to monitor both in natural waterways.

Student Responses (16)

Question 25

Written Paper Section I Question 25 - 2002 HSC

(a) Provide the systematic name of the CFC illustrated. (b) Identify the bonding within the ozone molecule, using a Lewis electron-dot diagram. (c) Discuss how CFCs damage the ozone layer, using relevant equations.

Student Responses (15)

Question 25-27

Written Paper Section I Question 25-27 - 2001 HSC

25. Explain the need for monitoring the products of a chemical reaction such as combustion. 26(a) Draw a graph using a fixed scale and data about lead concentrations. (b) Use the graph to interpret data. (c) State an hypothesis to account for variation in lead concentration observed. 27. Use a graph showing how ozone concentration changes with altitude to compare the environmental effects of the presence of ozone in the upper and lower atmosphere.

Student Responses (16)

Question 26

Written Paper Section I Question 26 - 2002 HSC

(a) Describe a test to determine whether a given sample of water is 'hard' or 'soft'. (b) Given the concentration of magnesium carbonate in a sample of hard water, calculate the mass, in mg, of magnesium carbonate in 150mL of this sample.

Student Responses (16)

Question 27

Written Paper Section I Question 27 - 2002 HSC

Describe the physical and chemical processes needed to purify and sanitise a town water supply.

Student Responses (14)

Band 5/6 response 1 Band 5/6 response 2 Band 5/6 response 3 Band 4/5 response 1 Band 4/5 response 2 Band 4/5 response 3 Band 3/4 response 1 Band 3/4 response 2 Band 2/3 response 1 Band 2/3 response 2 Band 2/3 response 3 Band 1/2 response 1 Band 1/2 response 2 Band 1/2 response 3

Question 29

Written Paper Section I Question 29 - 2010 HSC

(a) Assumptions made in a flowchart of the process to determine the amount of sulfate in a sample of lawn fertiliser. Explain how the assumptions affect the validity of the process. (b) Using the percentage composition of sulphate in the sample, determine the mass of the dried precipitate produced.

Student Responses (15)

Question 31

Written Paper Section I Question 31 - 2010 HSC

(a) Calculate the percentage of total dissolved solids in a filtered sample of dam water. Describe a chemical test to determine the presence of chloride ions in the sample. (b) Name an ion other than chloride that commonly pollutes waterways. Identify its source and the effect of its presence on water quality.

Component: Chemistry Skills

Student Responses (13)

Band 5/6 response 1 Band 5/6 response 2 Band 5/6 response 3 Band 4/5 response 1 Band 4/5 response 2 Band 4/5 response 3 Band 3/4 response 1 Band 3/4 response 2 Band 2/3 response 1 Band 2/3 response 2 Band 1/2 response 1 Band 1/2 response 2 Band 1/2 response 3

Question 21

Written Paper Section I Question 21 - 2010 HSC

Explain why solutions of hydrochloric acid and ethanoic acid with different concentrations have the same pH.

Student Responses (12)

Band 5/6 response 1 Band 5/6 response 2 Band 5/6 response 3 Band 4/5 response 1 Band 4/5 response 2 Band 3/4 response 1 Band 3/4 response 2 Band 3/4 response 3 Band 2/3 response 1 Band 2/3 response 2 Band 2/3 response 3 Band 1/2 response 1

Question 22

Written Paper Section I Question 22 - 2010 HSC

(a) Name a common use for the class of compounds to which methyl propanoate belongs. (b) Explain why reflux is necessary in the production of methyl propanoate. (c) Name and draw the structural formulae of the two reactants used to prepare methyl propanoate.

Student Responses (11)

Band 5/6 response 1 Band 5/6 response 2 Band 5/6 response 3 Band 4/5 response 1 Band 4/5 response 2 Band 4/5 response 3 Band 3/4 response 1 Band 2/3 response 1 Band 2/3 response 2 Band 1/2 response 1 Band 1/2 response 2

Question 23

Written Paper Section I Question 23 - 2010 HSC

(a) Write a balanced equation for the complete combustion of 1-butanol. (b) Given heats of combustion of three fuels in kJg-1 and that of 1-butanol in kJmol-1, justify which fuel is likely to be 1-butanol.

Student Responses (14)

Question 25

Written Paper Section I Question 25 - 2010 HSC

Describe the relationship between dissolved oxygen and biochemical oxygen demand. Explain why it is important to monitor both in natural waterways.

Student Responses (10)

Band 5/6 response 1 Band 5/6 response 2 Band 4/5 response 1 Band 4/5 response 2 Band 3/4 response 1 Band 3/4 response 2 Band 2/3 response 1 Band 2/3 response 2 Band 2/3 response 3 Band 1/2 response 1

Question 26

Written Paper Section I Question 26 - 2010 HSC

Calculate the volume of gas produced at 25°C and 100kPa when 10g of zinc is placed in 0.50 L of 0.2mol L-1 nitric acid.

Student Responses (15)

Question 28

Written Paper Section I Question 28 - 2010 HSC

Describe identified steps in a titration flowchart to determine the concentration of an unknown hydrochloric acid solution. Determine the concentration of hydrochloric acid used, given volume and concentration of a sodium carbonate standard solution.

Student Responses (14)

Question 29

Written Paper Section I Question 29 - 2010 HSC

Student Responses (14)

Band 5/6 response 1 Band 5/6 response 2 Band 4/5 response 1 Band 4/5 response 2 Band 4/5 response 3 Band 3/4 response 1 Band 3/4 response 2 Band 3/4 response 3 Band 2/3 response 1 Band 2/3 response 2 Band 2/3 response 3 Band 1/2 response 1 Band 1/2 response 2 Band 1/2 response 3

Question 30

Written Paper Section I Question 30 - 2010 HSC

(a) Compare the process of polymerisation of ethylene and glucose. (b) Explain the relationship between the structures and properties of three polymers from ethylene and glucose, and their uses.

Student Responses (15)

Question 31

Written Paper Section I Question 31 - 2010 HSC

Component: Option - Forensic Chemistry

Student Responses (2)

Exemplary response 1 Exemplary response 1

Question 32

Written Paper Section I Question 32 - 2002 HSC

(a) Identify the functional group in glycerol; compare reactions of glycerol and 1-propanol with cold dilute KMnO4. (b) Discuss the value of electron spectroscopy and scanning tunnelling microscopy in forensic chemistry analysis. (c) Identify the class of compounds used to break proteins into fragments of different lengths; describe the processes of electrophoresis and chromatography in separating organic compounds. (d) Outline the equipment and procedure used to analyse emission spectrum of sodium; explain how emission spectrum is produced. (e) Discuss uses of DNA analysis in forensic chemistry.

Component: Option - Industrial Chemistry

Student Responses (16)

Question 28

Written Paper Section I Question 28 - 2002 HSC

(a) Define saponification and account for the cleaning action of soap. (b) Calculate the equilibrium constant for a reaction used to form sulfuric acid. (c) Describe the reaction when sulfuric acid is added to water; using equations, describe the use of sulfuric acid as an oxidising agent, a dehydrating agent and as a means of precipitating sulfates. (d) Outline a procedure to investigate an equilibrium reaction; explain how the reaction can be analysed quantitively. (e) Evaluate changes in the industrial production methods for sodium hydroxide.

Student Responses (14)

Question 32

Written Paper Section II Question 32 - 2010 HSC

(a) Identification of one type of cell used in the extraction of sodium hydroxide. (b) Comparison of the electrolysis of molten sodium chloride and aqueous sodium chloride. (c) Graphical analysis of a system approaching equilibrium. (d) Process of saponification and specific safety precautions in a school laboratory. (e) Importance and environmental impacts of using limestone in the Solvay Process.

Component: Option - Shipwrecks, Corrosion and Conservation

Student Responses (16)

Question 29

Written Paper Section I Question 29 - 2002 HSC

(a) Type of electrochemical cell producing a spontaneous reaction; voltage required to operate an illustrated cell as an electrolytic cell. (b) How the work of early scientists increased our understanding of electron transfer reactions. (c) Method for removing salt from a shipwreck artefact; chemical procedures used to clean and preserve artefacts. (d) Procedure for comparing the rate of corrosion in different acidic and neutral solutions; explain whether data supports a hypothesis that acidic environments accelerate the corrosion of shipwrecks. (e) Analyse the effect of ocean depth on corrosion of metallic objects.

Student Responses (15)

Question 29

Written Paper Section II Question 29 - 2001 HSC

(a) Identify the main metal used to construct ships; explain why aluminium is used in structures exposed to oxidising conditions. (b) Identify a metal commonly used as a sacrificial anode; explain why sacrificial anodes are added to metal-hulled ships. (c) Describe the effect of adding other elements to iron on the properties and uses of steels. (d) Define corrosion;outline a procedure used to compare corrosion rates of different metals or alloys; describe ways accuracy and reliability of the procedure can be improved. (e) Evaluate steps used to clean, stabilise and preserve artefacts recovered from shipwrecks.

Student Responses (15)

Question 33

Written Paper Question 33 - 2010 HSC

(a) Effect of marine environment on a wood and metal artefact. (b) Labelled diagram to show electrolysis of an aqueous solution of potassium chloride, including identification of the cathode. (c) Explanation of how different composition of steel determine properties and uses. (d) Investigation of environmental factors affecting rate of corrosion of iron. Method to reduce effect of a corrosive factor in the marine environment. (e) Suitability of techniques for restoring and conserving wooden and copper artefacts that have been immersed in saltwater for at least 100 years.

Component: Option - The Chemistry of Art

Student Responses (1)

Exemplary response 1

Question 31

Written Paper Section I Question 31 - 2002 HSC

(a) Identify the metal ion that produces a yellow colour in a flame test; explain how some metal ions produce a colour in a flame. (b) Describe the bonding in a coordination complex. (c) Explain the term reflectance spectrum; outline how infrared and ultraviolet light are used to determine the chemical composition of pigments. (d) State the electronic configuration of manganese in terms of subshells; outline the procedure used to determine oxidising strength of potassium permanganate; justify a conclusion about oxidising strength of potassium permanganate. (e) Analyse trends in the physical properties of the first transition series.

Component: Production Of Materials

Question 1

Written Paper Section I Question 1 - 2002 HSC

Best conditions for the fermentation of sugars by yeast

Question 1

Written Paper Section I Question 1 - 2001 HSC

Type of reaction when ethene is converted into polyethene

Question 2

Written Paper Section I Question 2 - 2002 HSC

Catalyst for the conversion of ethanol to ethene

Question 2

Written Paper Section I Question 2 - 2001 HSC

Major component of biomass

Question 3

Written Paper Section I Question 3 - 2001 HSC

Equation best representing catalytic cracking of a petroleum fraction

Question 4

Written Paper Section I Question 4 - 2001 HSC

Correct representation of part of a cellulose polymer

Student Responses (13)

Question 16

Written Paper Section I Question 16 - 2002 HSC

(a) Name alkene used in first-hand investigation to compare its reactivity with its corresponding alkane. (b) Outline the procedure used in the investigation. (c) Describe the results obtained and include relevant chemical equations.

Student Responses (15)

Question 16-18

Written Paper Section I Question 16-18 - 2001 HSC

16. Relate the use of a named radioisotope to its properties. 17(a) Suggest sources of error in heat of combustion experiment. (b) Propose two means of reducing sources of error. (c) Using data given, calculate the molar heat of combustion of ethanol. 18(a) Complete a diagram of a galvanic cell. (b) Calculate the cell's theoretical voltage. (c) Explain why the use of a generator will cause the copper electrode to increase in mass. (Note that part (c) in no longer in the course.)

Student Responses (16)

Exemplary response 1 Band 5/6 response 1 Band 5/6 response 2 Band 5/6 response 3 Band 4/5 response 1 Band 4/5 response 2 Band 4/5 response 3 Band 3/4 response 2 Band 3/4 response 3 Band 3/4 response 1 Band 2/3 response 1 Band 2/3 response 2 Band 2/3 response 3 Band 1/2 response 1 Band 1/2 response 2 Band 1/2 response 3

Question 17

Written Paper Section I Question 17 - 2002 HSC

Explain why alkanes and their corresponding alkenes have similar physical properties, but very different chemical properties.

Student Responses (16)

Question 18

Written Paper Section I Question 18 - 2002 HSC

(a) Name the type of polymerisation shown in the chemical equation. (b) Assess current developments in the use of biopolymers.

Student Responses (16)

Question 19

Written Paper Section I Question 19 - 2002 HSC

(a) Describe the conditions under which a nucleus is unstable. (b) Describe processes by which an unstable isotope undergoes radioactive decay, using a flow diagram showing the sequence of products released during the decay of uranium.

Student Responses (15)

Question 19-21

Written Paper Section I Question 19-21 - 2001 HSC

19. Name and evaluate the effect of a type of galvanic cell in terms of chemistry and impact on society. 20(a) State one way in which pH can be measured. (b) Explain why solutions of equal concentrations of hydrochloric acid and citric acid have different pH values. 21(a) Name the type of reaction when barium hydroxide and sulfuric acid react. (b) Explain the changes shown in a graph measuring the conductivity of a sample of barium hydroxide when titrated with sulfuric acid. (Note that part (b) is not in the current course.)

Student Responses (11)

Question 23

Written Paper Section I Question 23 - 2010 HSC

Student Responses (12)

Question 24

Written Paper Section I Question 24 - 2010 HSC

(a) Write an equation using ethene for the hydrogenation of alkenes to convert unsaturated oils into solid fats. (b) Describe a test to confirm that all the ethene has been hydrogenated.

Student Responses (10)

Band 5/6 response 1 Band 5/6 response 2 Band 4/5 response 1 Band 4/5 response 2 Band 3/4 response 1 Band 3/4 response 2 Band 2/3 response 1 Band 2/3 response 2 Band 2/3 response 3 Band 1/2 response 1

Question 26

Written Paper Section I Question 26 - 2010 HSC

Calculate the volume of gas produced at 25°C and 100kPa when 10g of zinc is placed in 0.50 L of 0.2mol L-1 nitric acid.

Student Responses (10)

Band 5/6 response 1 Band 5/6 response 2 Band 5/6 response 3 Band 4/5 response 1 Band 4/5 response 2 Band 3/4 response 1 Band 3/4 response 2 Band 2/3 response 1 Band 2/3 response 2 Band 1/2 response 1

Question 27

Written Paper Section I Question 27 - 2010 HSC

Identify the anode, cathode and electrolyte for a given electrochemical cell with its relevant half equations.

Student Responses (14)

Question 30

Written Paper Section I Question 30 - 2010 HSC

(a) Compare the process of polymerisation of ethylene and glucose. (b) Explain the relationship between the structures and properties of three polymers from ethylene and glucose, and their uses.

Component: The Acidic Environment

Question 5

Written Paper Section I Question 5 - 2001 HSC

Substance that contributes most to the pH of unpolluted rainwater

Question 6

Written Paper Section I Question 6 - 2002 HSC

Identify an amphiprotic chemical using its formula

Question 6

Written Paper Section I Question 6 - 2001 HSC

Using a graph of colour ranges of three acid-base indicators and the colour of a solution in each indicator, identify the pH range of the solution.

Question 7

Written Paper Section I Question 7 - 2002 HSC

Reason for Brönsted's-Lowry's definition of acids being a significant improvement over earlier definitions

Question 7

Written Paper Section I Question 7 - 2001 HSC

Identification of common household acidic substance

Question 8

Written Paper Section I Question 8 - 2002 HSC

Substance used to rinse each piece of glassware used in a titration

Question 8

Written Paper Section I Question 8 - 2001 HSC

Given the equation for the burning of sulphur, calculate the volume of sulphur dioxide produced at 25° and 101.3kPa. (Note that molar volume is now reported using a pressure of 100kPa.)

Question 9

Written Paper Section I Question 9 - 2002 HSC

Four sequenced steps required for making an ester in a flask

Question 9

Written Paper Section I Question 9 - 2001 HSC

Prediction that can be made using Le Chatelier's principle

Question 10

Written Paper Section I Question 10 - 2002 HSC

Identify an equation representing esterification

Question 10

Written Paper Section I Question 10 - 2001 HSC

Given two equations describing the reactions in the formation of acid rain, identify what would occur if solid sodium sulfate were added to a sample of acid rain.

Student Responses (15)

Question 19-21

Written Paper Section I Question 19-21 - 2001 HSC

Student Responses (16)

Question 20

Written Paper Section I Question 20 - 2002 HSC

(a) Identify a common household base. (b) Assess the validity of a conclusion that all colourless solutions tested in an experiment were basic, using a table of results and a table of indicator colours at various pH levels.

Student Responses (13)

Band 5/6 response 1 Band 5/6 response 2 Band 5/6 response 3 Band 4/5 response 1 Band 4/5 response 2 Band 4/5 response 3 Band 3/4 response 1 Band 3/4 response 2 Band 2/3 response 1 Band 2/3 response 2 Band 1/2 response 1 Band 1/2 response 2 Band 1/2 response 3

Question 21

Written Paper Section I Question 21 - 2010 HSC

Explain why solutions of hydrochloric acid and ethanoic acid with different concentrations have the same pH.

Student Responses (16)

Question 21

Written Paper Section I Question 21 - 2002 HSC

Evaluate the impact of industrial sources of sulfur dioxide and nitrogen oxides on the environment, making use of appropriate chemical equations.

Student Responses (12)

Question 22

Written Paper Section I Question 22 - 2010 HSC

Student Responses (16)

Question 22

Written Paper Section I Question 22 - 2002 HSC

(a) Calculate the pH of a hydrochloric acid solution, given equal concentrations of hydrochloric acid, sulfuric acid and acetic acid and a known pH for the acetic acid. (b) Compare the pH values of the sulfuric acid and hydrochloric acid solutions. (c) Explain why the acetic acid solution has a higher pH than the hydrochloric acid solution.

Student Responses (15)

Question 22-24

Written Paper Section I Question 22-24 - 2001 HSC

Student Responses (16)

Question 23

Written Paper Section I Question 23 - 2002 HSC

(a) Identify the gas released when the cap is removed from a bottle of soft drink. (b) Given a graph showing how the mass of cap, bottle and contents changes over time, calculate the volume of gas released at 25°C and 101.3kPa (Note: since 2003 HSC, molar volume is expressed at 100kPa).

Student Responses (15)

Question 25-27

Written Paper Section I Question 25-27 - 2001 HSC

Student Responses (10)

Band 5/6 response 1 Band 5/6 response 2 Band 4/5 response 1 Band 4/5 response 2 Band 3/4 response 1 Band 3/4 response 2 Band 2/3 response 1 Band 2/3 response 2 Band 2/3 response 3 Band 1/2 response 1

Question 26

Written Paper Section I Question 26 - 2010 HSC

Calculate the volume of gas produced at 25°C and 100kPa when 10g of zinc is placed in 0.50 L of 0.2mol L-1 nitric acid.

Student Responses (15)

Question 28

Written Paper Section I Question 28 - 2010 HSC