Earth and Environmental Science 2019 HSC exam pack

Students should:

• plan their answers to assist in the logical structuring of the response to the question
• integrate relevant specific terminology into the responses rather than using generalised terminology
• identify the key words in the question such as ‘Evaluate’, ‘Account’ and answer accordingly.

Question 21

In better responses, students were able to:

• demonstrate their knowledge and understanding of sustainability by defining the concept and linking the reasons why processes used by Aboriginal Peoples or Torres Strait Islander Peoples were or were not sustainable
• describe in detail two or more examples of processes used by Aboriginal Peoples or Torres Strait Islander Peoples, then make a judgement of their sustainability
• provide multiple links within or between each example they used to demonstrate their depth of understanding of the sustainability of processes used by Aboriginal Peoples or Torres Strait Islander Peoples.

Areas for students to improve include using:

• appropriate terminology to link processes and examples to sustainability.

Question 22

In better responses, students were able to:

• refer to types of solid household waste, including but not limited to, organic/green waste, recyclable and non-recyclable materials
• summarise the main processes involved in managing different types of household solid waste
• provide some detail about each of the processes
• construct an organised flow chart using arrows.

Question 23

In better responses, students were able to:

• graph data clearly and accurately using the scale provided (a)
• correctly identify different aspects of the graph by using the key (a)
• use the formula appropriately to correctly generate the calculations required to complete the table (b)
• identify from the table the material with the lowest percentage total recovery (PTR) and justify a strategy used to improve the recovery rate of the material (c)
• clearly describe the strategy that could be used to improve the recovery rate of recycled materials, including but not limited to cashback incentives for returning empty bottles (c).

Areas for students to improve include:

• constructing graphs using a ruler and noting the scale provided to ensure accuracy (a)
• ensuring all numbers in a table are correctly rounded off to the same number of decimal places (b)
• clearly justifying their strategy to improve the recovery rate (c).

Question 24

In better responses, students were able to:

• engage with the stimulus material provided with the question to  help connect the pieces of information required to relate the cross section with the geological time scale data sheet; use the graph and table of fossils to accurately determine the ages of the different layers in the cross section, demonstrating their understanding of relative and absolute dating techniques (a)
• demonstrate their ability to implement the working scientifically skills linked to processing, extracting and communicating data from a variety of stimulus formats (a)
• correctly name missing geological periods (a)
• access the geological time scale provided on the data sheet appropriately (a)
• demonstrate their knowledge and understanding of both the principle of cross cutting relationships and the law of superposition when justifying the age of Unit 7 (b)
• correctly use syllabus terminology linked to relative and absolute dating
• link position of units 6,7,8 and 10 to the likely age of Unit 7 (b).

Areas for students to improve include:

• extracting accurate data from graphs (a)
• recognising and understanding specific terminology used in stimulus materials (a)
• understanding the principle of cross cutting relationships in strata (a)
• linking age to stratigraphic position and the processes of cross cutting and superposition (b).

Question 25

In better responses, students were able to:

• identify repetition for first-hand investigations and make clear links between consistency and/or similarity of data.

Areas for students to improve include:

• demonstrating a clear understanding of reliability and not relating the question to validity of first-hand investigations
• avoiding the use of calculating averages to improve reliability if results are not consistent.

Question 26

In better responses, students were able to:

• engage with the stimulus material and apply the various numeric scales to each component of the graph
• demonstrate their knowledge and understanding of the development of the biosphere, namely photosynthetic bacteria, and relate the cause and effect relationship to the deposition of banded iron formations in the hydrosphere
• demonstrate their knowledge and understanding of the changes in the atmosphere due to the biosphere, as oxygen reached saturation and dissolved iron salts were precipitated from the hydrosphere, and oxygen was then free to move into the atmosphere
• demonstrate their knowledge of the reduction of carbon dioxide concentration from the atmosphere by the biosphere
• reference numeric data sets to support their answer.

Areas for students to improve include:

• answering the question asked and making reference to the stimulus material
• using numeric data to support their answer
• applying knowledge of the biosphere by using the correct scientific terminology, for example, cyanobacteria not stromatolites
• using cause-and-effect relationships to explain phenomena.

Question 27

In better responses, students were able to:

• use numerical data provided in the question
• relate the iridium content to a layer near an impact site being higher than the above and below layers of crustal rock
• compare iridium in rocks and meteorites, and make a link to a mass extinction
• make a link to how the data can be used to support the proposed theory.

Areas for students to improve include:

• making links to cause and effect obvious in their response
• engaging with the stimulus material provided to guide the response.

Question 28

In better responses, students were able to:

• relate the cause and effect of both disasters and provide several characteristics about the effects
• use terminology specific to each hazard
• identify that mass water displacement was required for a tsunami wave to form
• outline lahars as ash and debris flows associated with volcanic eruptions and an influx of water from a variety of sources, including but not limited to melting snow on the crater edge, crater lake spill over or extreme weather events such as cyclones occurring in the area.

Areas for students to improve include:

• using scientific terminology to describe and explain the disasters
• using diagrams to assist in relating causes and effects.

Question 29

In better responses, students were able to:

• demonstrate their knowledge and understanding of technologies used in meteorology to predict extreme weather events
• evaluate (with criteria and assessment) at least two different technologies
• show knowledge of the general characteristics of extreme weather events.

Areas for students to improve include:

• using specific examples rather than making general comments
• recognising that more than one technology was required
• understanding the difference between extreme tectonic and extreme weather events.

Question 30

In better responses, students were able to:

• link each boundary type to the depth at which earthquakes occur (a)
• account for (by providing a reason) why earthquakes occur at each boundary (a)
• demonstrate sound knowledge and understanding of both types of volcanism and their effects on both the biosphere and the atmosphere (b)
• compare the effects of both types of volcanism on both the biosphere and the atmosphere (b).

Areas for students to improve include:

• showing their specific knowledge of boundary characteristics rather than making general comments (a)
• making effective use of the table provided to compare the effects (b)
• showing their specific knowledge and understanding rather than making general comments (b).

Question 31

In better responses, students were able to:

• identify that the climate has always fluctuated due to natural occurrences
• distinguish between natural and anthropogenic climate change
• demonstrate understanding that we cannot stop the natural causes but can manipulate the anthropogenic causes
• outline numerous reasons why scientists are studying the current trend
• include rates and time frames for the change rather than just stating the ‘increasing CO₂’ from the question, including the slow gradual change over a long period of time for natural, and rapid change over a shorter time frame for the current trend
• provide concrete reasons for investigating the difference and linking investigations to the fact that although we cannot stop nature, we can mitigate our own contributions.

Areas for students to improve include:

• addressing all parts of the question, the natural causes as well as the anthropogenic causes
• focusing on reasons and linking the two together, rather than focusing only on one aspect
• drawing an example graph and annotating it to support their answer.

Question 32

In better responses, students were able to:

• identify that carbonic acid is produced (a)
• explain the relationship between atmospheric and hydrospheric CO₂ levels (a)
• link an increase in atmospheric CO₂ to an increase in ocean absorption of CO₂, and then link carbonic acid to a decrease in pH (a)
• show a clear understanding of the process as a flow-on effect of anthropogenic  increases in atmospheric CO₂ emission and how this interacted with ocean water to form increased carbonic acid, lowering overall ocean pH (a)
• describe a specific impact, for example, calcium carbonate shells dissolving, instead of a general statement, for example, fish species die (b)
• elaborate an effect by indicating why coral bleaching occurred or linked shell destruction to death (b)
• describe the chemical reaction between weak acid in the ocean and calcium carbonate in shells, including that with coral bleaching there will be the loss of food and habitat for dependent species in the ecosystem (b).

Areas for students to improve include:

• understanding the pH scale (a)
• using cause and effect in the response (a)
• avoiding a focus on generic responses like ‘everything died’ or talking about temperature effects instead of pH (b).

Question 33

In better responses, students were able to:

• use examples as evidence to support their knowledge and understanding of the changing biodiversity in Australia over time depicted in Aboriginal artwork, such as:
  • making links with changes in types of organisms depicted in Aboriginal art over time OR no longer appearing
  • explaining high diversity changing to low diversity over time, sighting older artworks versus younger works
  • noting the presence and then absence of megafauna
  • noting changes in species from terrestrial to aquatic over time, for example, carvings can be traced to show changes in art; land animals giving way to depictions of marine species over time due ice melting and sea levels rising (a)
• demonstrate their knowledge and understanding of sedimentary rocks and their indicators of past environments based on the principle of uniformitarianism and the environments we find the sediments occupy today (b)
• clearly link named examples to a specific environmental condition and to a specific sedimentary rock (b)
• provide two or more examples of sedimentary rocks found in each environment, for example, limestone formed from fossilised coral reefs, indicating a shallow, tropical marine environment, which is where coral reefs form today (b).

Areas for students to improve include:

• avoiding using general comments relating to changing environments by identifying the changes in named species (a)
• demonstrating a clear understanding of the processes involved in the formation of sedimentary rocks (b)
• avoiding general comments relating to an indication of past environments by using a specific example linked to a specific environmental condition (b)
• clearly linking isotopic ratios to specific climatic conditions (b).

Question 34

In better responses, students were able to:

• refer to a specific geoengineering strategy, such as but not limited to, carbon sequestration
• outline positives and/or negatives of the strategy and make an effective judgement
• demonstrate the difference between mitigation and adaptation
• describe concrete geo-engineering strategies and link these to a reduction in solar radiation or CO₂ levels, while also giving a concrete value/judgement.

Areas for students to improve include:

• recognising the difference between mitigation and adaptation
• understanding the difference between geo-engineering, geo-design, agriculture and alternative energy to select the most appropriate strategy for the category chosen within the question.

Question 35

In better responses, students were able to:

• identify and explain specific examples of anthropogenic environmental problems
• specify working scientifically skills synonymous with the course outcomes and provide details of how they were applied in BOTH investigating and developing solutions to the identified problems.

Areas for students to improve include:

• describing the practices and process of working scientifically
• providing breadth and depth of knowledge about the range of anthropogenic environmental problems.