A Sphere Made of a Radioactive Isotope Initially Has a Mass

question 55

Multiple Choice

A sphere made of a radioactive isotope initially has a mass of 6.88 kg.The half-life of this isotope is 1.34 h,and it decays by β^- emission.At the end of 2.68 h,what is the mass of this sphere?

• A) 6.88 kg
• B) 3.44 kg
• C) 1.72 kg
• D) 2.53 kg

---

Definitions:

Psychodynamic Theory

A psychological perspective that emphasizes unconscious processes and childhood experiences in shaping personality and behavior.

Carl Jung

A Swiss psychiatrist and psychoanalyst who founded analytical psychology and contributed significantly to the understanding of the psyche.

Inferiority Complex

A psychological condition marked by feelings of inadequacy and insecurity, often stemming from real or imagined comparisons to others.

Alfred Adler

An Austrian medical doctor and psychotherapist, a pioneer in individual psychology emphasizing the importance of feelings of inferiority and the creative self.