Arsenic, Which Is Toxic, Can Be Removed from Drinking Water

question 5

Essay

Arsenic, which is toxic, can be removed from drinking water by precipitation as the sulfide. Write the net ionic equation for the precipitation of As³⁺ using sodium sulfide, Na₂S.

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Definitions:

Pediatrician

A medical doctor specializing in the physical, behavioral, and mental care of children from birth until adolescence.

Slow-wave Sleep

A deep sleep phase characterized by slow brain waves, important for physical restoration and memory consolidation.

REM Sleep

Rapid Eye Movement (REM) sleep is a unique phase of sleep characterized by fast movements of the eyes, vivid dreams, and increased brain activity.

Paradoxical Sleep

Another term for REM (Rapid Eye Movement) sleep, a phase of sleep during which the brain is active and dreams occur, but the body remains paralyzed.