What Metals Occur in the Free and Uncombined State and Are

question 63

Essay

What metals occur in the free and uncombined state and are obtained by roasting their sulfides?

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Definitions:

Autotrophs

Organisms that can produce their own food from inorganic substances using light (photosynthesis) or chemical energy (chemosynthesis).

Heterotrophs

Organisms that cannot synthesize their own food and rely on other organisms — either plants or animals — for nutrition.

Nutrient

Substances obtained from food necessary for growth, metabolism, and for other body functions.

Ecosystem

Biological community together with the associated abiotic environment; characterized by a flow of energy and a cycling of inorganic nutrients.