What Is the Half-Life of a Radioactive Substance If 2

question 61

Multiple Choice

What is the half-life of a radioactive substance if 2.9 g decays to 1.80 g in 64 hours? Round to the nearest tenth of an hour.

• A) 93.0 hours
• B) 69.8 hours
• C) 46.5 hours
• D) 23.3 hours
• E) 13.8 hours

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Definitions:

Initiative Vs. Guilt

A stage of psychosocial development in Erik Erikson's theory where children learn to initiate activities and interact with others or feel guilty for being unsuccessful at these tasks.

Object Permanence

is the cognitive understanding that objects continue to exist even when they cannot be seen, heard, or otherwise sensed, a fundamental concept in developmental psychology.

Sensory-Motor Stage

The earliest stage in Piaget's theory of cognitive development, where infants learn about the world primarily through their senses and motor activities.

Egocentrism

A cognitive trait that describes the inability to differentiate between one's own perspective and another person's perspective, often seen in early childhood development.