A Condition Characterized by Normal Development for at Least 2

question 28

Multiple Choice

A condition characterized by normal development for at least 2 and up to 10 years, followed by a significant loss of skills is

• A)Asperger syndrome.
• B)Rett syndrome.
• C)childhood disintegrative disorder.
• D)pervasive developmental disorder.

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Definitions:

Hydrogen Ion Concentration

A measure of the acidity or alkalinity of a solution, often expressed in terms of pH.

pH

A measurement system designed to indicate the level of acidity or alkalinity in water-based solutions, ranging from 0 (highly acidic) to 14 (highly alkaline), with the midpoint, 7, representing a neutral pH.

Buffer

A solution that resists changes in pH when acid or alkali is added to it.

Ionic Substance

A chemical compound composed of ions held together by electrostatic forces termed ionic bonding, typically formed when a metal reacts with a nonmetal.