Explain that metal ores are limited resources.

In the subtopic Alternative methods of extracting metals, this learning objective focuses on explain that metal ores are limited resources. Within Using the Earth's resources and obtaining potable water, students should explain this idea in the exact curriculum context rather than as an isolated fact. Approved keywords for this objective include limited resources. metal ores means naturally occurring solid materials from which metals can be extracted. Avoid students often think that metal ores are unlimited resources and can be extracted indefinitely; instead emphasize that metal ores are finite resources, meaning they are limited in availability and will eventually be depleted. For exam answers, remember that metal ores are finite resources; focus on the implications of this in your answers.