The Argon-40 Method of Radioisotope Dating, Which Was Developed to Determine

question 113

Essay

The argon-40 method of radioisotope dating, which was developed to determine the age of moon rocks, assumes that no 40Ar gas was trapped when the molten rock solidified and that no 40Ar could escape from the solid rock.Potassium-40 decays into argon-40 by positron emission with a half-life of 1.28 * 10⁹ years.One sample of moon rock showed a ratio of 40K to 40Ar of 0.100 N_K/N_Ar = 0.100).How many years ago was this moon rock formed?

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Definitions:

Family Systems Therapy

Psychotherapy that focuses on the family, rather than the individual, as the source of problems; family therapists challenge communication styles, disrupt pathological family dynamics, and challenge defensive conceptions in order to harmonize relationships among all members and within each member.

Belief System

A set of principles or tenets which together form the basis of a person's convictions, values, and attitudes.

Cultural Definition

The way in which individual concepts, practices, and values are understood and shared within a specific culture.

Third-Wave Approaches

Modern psychotherapeutic techniques that combine elements of the first- and second-wave approaches—behavioral therapy and cognitive therapy, respectively—with mindfulness meditation practices derived from Zen Buddhism to help people accept, understand, and better regulate their emotions.