The Time It Takes for 50% of an Unstable Isotope

question 10

Multiple Choice

The time it takes for 50% of an unstable isotope to decay to a stable form is called the

• A) semichron.
• B) middlemorph.
• C) demidose.
• D) half-life.

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Definitions:

Cognitive Development

The study of how thinking, problem solving, and reasoning skills evolve through childhood and adolescence.

Jean Piaget

A Swiss psychologist known for his pioneering work in the field of developmental psychology, especially his theory of cognitive development in children.

Developmental Changes

Refers to the biological, psychological, and emotional changes that occur in human beings between birth and the end of adolescence.

Physical Changes

Alterations in the form, appearance, or structure of a substance without changing its chemical composition.