ÐÇ¿Õ´«Ã½

Kia ora and welcome.  

This webcast is intended to provide guidance and advice on the requirements for Chemistry and Biology Level 1 Achievement Standard 92021: Demonstrate understanding of chemical reactions in context.   

Specifically, this webcast will explore the requirement for students to relate the evidence of three chemical reactions in context.

The title of the standard and the criteria for each level of achievement show that the understanding of chemical reactions needs to relate to the chosen context.  

The context for each reaction type needs to be consistent through all the evidence for that specific reaction type.

Evidence that uses a different reaction from the context reaction does not meet the requirements of the standard.

Explanatory Note 3 of the standard elaborates on what is meant by ‘context.’ The context needs to be an example of the reaction type that occurs beyond the laboratory.

While the task may refer to the reaction as seen in the lab, the evidence used to meet the standard needs to be related to the specific reaction involved in the chosen context.

For example, a neutralisation reaction may be assessed in the context of antacids.

The predictable pattern and observations need to be related to the context of using antacids to treat indigestion.

While the lab demonstration might involve the use of indicators to show how the acidity of the solution changes during the reaction, this may not be a relevant observation in the context of using antacids for indigestion.

The observation of burping for a carbonate-based antacid could be a relevant observation for the antacid context. Similarly, a combustion reaction in the context of a camp stove needs to link the reaction type to the specific context.

This could use the observation of soot forming on the bottom of the pan, resulting from the products of the incomplete combustion of the fuel.

If the reaction was modelled in the lab, observations from any testing, such as using cobalt chloride paper to confirm the presence of water, may not link directly to the chosen context of a camp stove.

For more explanation and examples of what is required for this criterion, see the exemplars on the ÐÇ¿Õ´«Ã½ website.

Further assessor support for the internal Achievement Standards in Chemistry and Biology can be found in our assessor support catalogue available on the ÐÇ¿Õ´«Ã½ website. 

Thank you.