Science Extension 2022 HSC exam pack

Students should:

• read the question carefully to ensure that they do not miss important components of the question
• have a clear understanding of key words in the question and recognise the intent of the question and its requirements
• plan the response to assist in the logical sequencing of information
• communicate ideas and information using appropriate scientific language
• engage with any stimulus material provided and refer to it in their response
• show all working in calculations and include correct units
• present a logical and coherent response that addresses the question
• review their response to ensure that it addresses the question requirements
• review their response to ensure there are no contradictions
• monitor the time to allow for the level of critical analysis required to plan each response.

Question 1

In better responses, students were able to:

• explain the process of data collection and analysis specifically from the image
• incorporate examples from the stimulus into the response to demonstrate content analysis
• describe the process of identifying the qualitative data then how to quantify this data.

Areas for students to improve include:

• focusing on the key elements of the question, such as content analysis
• avoiding assumptions about what can be measured by visual data, for example, you cannot measure yield over time from an image
• focusing on the area being asked to collect information from, rather than extending to other areas not in the question, for example, not collecting data other than that in the image.

Question 2

In better responses, students were able to:

• demonstrate a clear understanding of the features of the data that allow a t-test to be used
• provide clear methods that enabled the students to have confidence the data may be used in a t-test
• focus on the data rather than the use of the Student’s t-test.

Areas for students to improve include:

• identifying the stage of the process of the analysis; that is, checking the validity of the source data, not the use of the t-test
• selecting features of the data that can be verified rather than referring to the methodology of the investigation
• providing specific requirements for use of the data in the Student's t-test rather than general assumptions related to any statistical analysis.

Question 3

In better responses, students were able to:

• discuss the nature of paradigm shifts in relationship to changes in scientific understanding
• use clear examples to support how science knowledge develops
• make a clear, valid judgement based on their evidence.

Areas for students to improve include:

• identifying relevant examples from their range of knowledge about scientific discoveries or research
• linking examples to the judgement.

Question 4

In better responses, students were able to:

• integrate the analysis of both data sources to support a judgement
• critically analyse the source data in a systematic manner
• recognise the limitations of the data in the sources in supporting a judgement.

Areas for students to improve include:

• connecting appropriate information from the source to the question, for example, connecting the legislation to both sources and then incorporating the analysis into the response
• analysing source data in full rather than describing it
• ensuring the connections made between the sources are justified from the data in the sources.

Question 5

In better responses, students were able to:

• interpret a graph to correctly identify the relationships being measured (a)
• describe the relevance of the correlation coefficient and the gradient in comparing the satellite and ground methods (a)
• demonstrate a clear distinction between the requirements for correlation and causation (b)
• provide an argument and conclusion for how data can be used to show causation as well as correlation (b).

Areas for students to improve include:

• describing how the regression coefficient and the gradient can be used to assess the confidence in a relationship (a)
• providing a conclusion about the use of the satellite data rather than use of fluorescence from photosynthetic chlorophyll (FPC) data in general (a)
• identifying the relationship specified in the question, rather than the relationship being described in a source (b)
• demonstrating an analysis of all the stimulus, rather than focusing on a single source (b)
• demonstrating an understanding of the key elements required to show causation (b).

Question 6

In better responses, students were able to:

• link all aspects of the stimulus to their response and use it to support their judgement
• effectively relate the purpose of predictive models to the sources.

Areas for students to improve include:

• identifying the difference between data collected in a literature study to design a model, rather than data collected from a model
• showing points for an argument such as limitations and strengths of a model
• understanding the role of modelling in the scientific process.

Question 7

In better responses, students were able to:

• identify the relevant points from the slides and then critically analyse the points against all listed considerations, including drawing out implications and limitations
• relate implications of their analysis to the relevant processes of scientific research.

Areas for students to improve include:

• only including references to their own scientific research project if it is relevant and enhances the response
• analysing the stimulus’ considerations rather than just identifying them
• recognising that analysis of data is required before being able to assess reliability, rather than just collection of multiple samples by repetition
• using scientific terms such as validity and accuracy in their response and only using the terms if it adds value to the response.