When Phosphate Rock, Ca₃(PO₄)₂(s), Is Converted to Phosphorus

question 48

Multiple Choice

When phosphate rock, Ca₃(PO₄) ₂(s) , is converted to phosphorus,

• A) one of the products of the reaction is water.
• B) sulfuric acid is added to generate insoluble calcium sulfate.
• C) hydrogen is used to reduce the phosphate to phosphorus.
• D) silica is added to form a calcium silicate slag.
• E) oxygen must be added to prevent reaction of P₄.

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Definitions:

Thalamus

A part of the brain that serves as a relay station, transmitting information between different areas of the brain.

Hypothalamus

A region of the brain that coordinates many activities, including temperature regulation, thirst, hunger, and emotional activity.

Diencephalon

The between brain, which integrates sensory and motor information on its way to the cerebral cortex.

Mesencephalon

Also known as the midbrain, it is a portion of the brainstem involved in vision, hearing, motor control, sleep/wake, arousal, and temperature regulation.