In Which of the Following Zones Is a False-Negative Reaction

question 20

Multiple Choice

In which of the following zones is a false-negative reaction likely?

• A) prozone
• B) zone of equivalence
• C) postzone
• D) all of the above

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Definitions:

Obsidian

A generally gray to black, shiny volcanic glass, usually of felsic composition.

Andesite

A volcanic rock of intermediate composition, typically found in volcanic arcs associated with subduction zones.

Volcanic Domes

Rounded, bulbous formations of lava that accumulate near and around volcanic vents, often resulting from the slow extrusion of viscous lava.

Volcanic Glass

A type of rock that forms from the rapid cooling of magma without crystallization, resulting in a smooth, glassy texture.