Some natural (raw) materials can be used in their original state
Manufactured (processed) materials are raw materials that have been changed from their natural state into a new state
EXAMPLE QUESTIONS
What natural materials do you use?
What materials do you use that have been manufactured?
How are manufactured materials different from natural materials?
SOME MATERIALS ARE NATURAL
Raw materials are those natural materials that exist in the world, unchanged by humans, such as wood, coal, rock, water, air and bone etc
People and animals make use of natural materials for a variety of purposes.
Many of these purposes require the material to be adapted for use (for example, cut, shaped or secured), but the state of the material itself is not changed.
Although many raw materials, such as trees, replenish naturally, it can take a long time.
Some raw materials may disappear from the Earth unless consumption of them is carefully managed.
SOME MATERIALS ARE MANUFACTURED
People have discovered ways of changing natural materials into other useful materials.
Heating or cooling can change some materials either temporarily or, in some cases, permanently.
Heating can make some materials melt.
Cooling can make some material solidify.
Some materials can be changed by being combined through a chemical reaction, which then produces a new material.
Manufactured materials are those that have been changed from raw materials into new materials.
People make use of a wide variety of manufactured materials for numerous purposes.
