Phenol Red Indicator Changes from Yellow to Red in the PH

question 41

Multiple Choice

Phenol red indicator changes from yellow to red in the pH range from 6.6 to 8.0. State what color the indicator will assume in the following solution: 0.10 M NH₄NO₃

• A) red
• B) yellow
• C) red-yellow mixture
• D) The indicator is its original color.
• E) There is not enough information to answer this question.

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Definitions:

Green Afterimage

A visual phenomenon where exposure to a green stimulus leads to the perception of a red afterimage when the stimulus is removed, due to the adaptation of photoreceptors.

Opponent-Process Theory

Opponent-Process Theory is a psychological and neurological model that explains how humans perceive colors as the result of complex processes involving opposing responses of color pairs.

Young-Helmholtz Theory

A theory of color vision proposing that the eye perceives colors through the response of three different kinds of cones, each sensitive to red, green, or blue light.

Opponent-Process Theory

A theory that suggests emotions are regulated by mechanisms that operate in opposing pairs, such as pleasure and pain or fear and relief.