Question

Which of the following is an example of an element found in its pure (native) form in nature?

• A. Sodium
• B. Graphite
• C. Magnesium
• D. Calcium

Answer 1

Answer:

B. Graphite

Native Elements in Geology

Native elements are chemical elements that exist in their pure, uncombined form in nature. They are not found as compounds with other elements.

Graphite as a Native Element

• Graphite is a naturally occurring allotrope of carbon. Allotropes are different structural forms of the same element in the same physical state.
• It is one of the softest known natural minerals, which makes it useful as a lubricant and in pencils.
• Graphite is primarily composed of carbon atoms arranged in a hexagonal lattice structure.
• Its formation often occurs under conditions of high pressure and temperature, typically deep within the Earth's crust or in metamorphic rocks.
• Other common examples of native elements include:
• Gold (Au): Often found in veins of quartz or as placer deposits.
• Silver (Ag): Can be found alongside copper or in mineral veins.
• Copper (Cu): Occasionally found in its pure metallic form, especially in certain ore deposits.
• Diamond (C): Another allotrope of carbon, known for its extreme hardness and found in kimberlite pipes.
• Sulfur (S): Typically found near volcanic regions or in sedimentary deposits.

Formation and Occurrence

• The conditions under which native elements form are crucial for their existence in a pure state. They must form in environments where reactions with other elements are minimized.
• The Earth's crust contains a significant number of native elements, though they are often rare and concentrated in specific geological settings.
• Geologists study native elements as indicators of the geological processes and conditions present during their formation.