NCEA

Chemistry- annotated exemplars level 1 AS90931

Demonstrate understanding of the chemistry in a technological application (1.2)

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TKI Chemistry Assessment Resources	Download all these exemplars and commentary (PDF, 139KB)

Low Excellence

Commentary

Student response
Student 1 (PDF, 36KB)

For Excellence, students are expected to demonstrate comprehensive understanding of the chemistry in a technological application.

This typically involves linking the chemistry applicable to the chosen application with its use. The linking may include explaining, elaborating, justifying, relating, evaluating, comparing and contrasting, or analysing.

The student has provided an account of the chemistry related to setting of cement (1). An explanation of how the chemistry applies to the use of cement is given (2). The chemistry involved in the setting of hydraulic and non-hydraulic cement is linked by comparing and contrasting how the two types of cement set (2).

To reach Excellence more securely, the student would need to elaborate on the chemistry involved by writing relevant equations for the chemical reactions that occur when hydraulic and non-hydraulic cement set (3) and (4).

High Merit

Commentary

Student response
Student 2 (PDF, 35KB)

For Merit, students are expected to demonstrate in-depth understanding of the chemistry in a technological application.

This typically involves explaining how or why the chemistry applies to the use of the chosen application.

The student has demonstrated in-depth understanding by providing an account of the chemistry related to setting of cement (1). An explanation of how the chemistry applies to the use of cement is given (2).

To reach Excellence, the student would need to link the chemistry applicable to cement by elaborating: writing a chemical reaction for the setting of hydraulic cement and comparing and contrasting the setting of hydraulic and non-hydraulic cement (3).

Low Merit

Commentary

Student response
Student 3 (PDF, 33KB)

For Merit, students are expected to demonstrate in-depth understanding of the chemistry in a technological application.

This typically involves explaining how or why the chemistry applies to the use of the chosen application.

The student has given an explanation of how the chemistry applies to hydraulic Portland cement. There is discussion of the chemistry involved in the hardening process (1).

To reach Merit more securely, the student would need to explain how non-hydraulic cement hardens and thus give a more detailed explanation of how the chemistry applies.

High Achieved

Commentary

Student response
Student 4 (PDF, 33KB)

For Achieved, students are expected to demonstrate understanding of the chemistry in a technological application.

This typically involves providing characteristics of, or an account of, the chemistry related to the use of the chosen application.

The student has demonstrated understanding by providing an account of the chemistry related to the use of both hydraulic and non-hydraulic cement is provided (1).

Characteristics of the chemistry related to the hardening of cement are also provided (1).

To reach Merit, the student would need to explain how or why the chemistry applies to the use of Portland cement.

Low Achieved

Commentary

Student response
Student 5 (PDF, 33KB)

For Achieved, students are expected to demonstrate understanding of the chemistry in a technological application.

This typically involves providing characteristics of, or an account of, the chemistry related to the use of the chosen application.

The student has provided an account of the chemistry related to the use of hydraulic cement (1). Characteristics of the chemistry related to the hardening of hydraulic cement are also provided (1).

To reach Achieved more securely, the student would need to give an account and provide characteristics of both hydraulic and non-hydraulic cement.

High Not Achieved

Commentary

Student response
Student 6 (PDF, 33KB)

For Achieved, students are expected to demonstrate understanding of the chemistry in a technological application.

This typically involves providing characteristics of, or an account of, the chemistry related to the use of the chosen application.

The student has made an attempt to provide an account of the chemistry related to the use of Portland cement (1).

To reach Achieved, the student would need to provide a more detailed account of the chemistry related to the use of Portland cement.