Our Planet Earth

Unit Overview

This Unit focuses on how to obtain useful chemicals from the atmosphere, oceans and Earth's crust using various extraction and separation methods. Students will learn about the carbon cycle, and also learn about carbon dioxide removal and storage technologies (e.g. forestation, biochar, direct air capture) to understand the important role of these methods in mitigating the greenhouse effect, and realise the concept of “change and constancy”. Students will also learn some simple chemical tests and extraction methods, and practice scientific observation, measurement and inference by conducting different experiments, such as flame tests. Students will practice the use of word equations or chemical equations to express the chemical changes that occur during the metal extraction process of metal ores. In addition, students will realise that chemicals extracted from the Earth can be used to produce useful materials, which are widely used in the modern world to enhance quality of life. However, students should also be aware that improper use and disposal of these materials will cause environmental pollution and the exhausting of resources. Students can conduct cross- disciplinary project learning to explore scientific issues related to sustainable development, such as discussing how the development of new plastic materials can balance social needs and ecological conservation. These learning activities help students understand sustainable development and cultivate the proper values of protecting the environment. Teachers can also design other appropriate learning and teaching activities to enable students to develop and master the following skills: a) using specific data to induce a general trend, conclusion or model b) using a set of general observations, trend or model to deduce a specific result c) making inference to the best possible explanation to the observed phenomenon d) formulating a hypothesis based on observed phenomenon e) identifying independent variables, dependent variables and control variables f) making qualitative observations and quantitative measurements g) identifying causation h) choosing from alternative experimental methods or improving the method for a scientific investigation i) commenting the reliability of a scientific measurement or a scientific investigation j) using tables and graphs for data analysis k) referencing reliable sources of information l) evaluating the balance between modernisation and environmental cost m) evaluating the impact of scientific and technological discoveries on the quality of life