Carbon-12 Is the Most Common Isotope of Carbon, and Has

question 77

Multiple Choice

Carbon-12 is the most common isotope of carbon, and has an atomic mass of 12 daltons. A mole of carbon in naturally occurring coal, however, weighs slightly more than 12 grams. Why?

• A) The atomic mass does not include the mass of electrons.
• B) Some carbon atoms in nature have an extra proton.
• C) Some carbon atoms in nature have more neutrons.
• D) Some carbon atoms in nature have a different valence electron distribution.
• E) Some carbon atoms in nature have undergone radioactive decay.

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Definitions:

Defense Mechanism

Psychological strategies brought into play by the unconscious mind to manipulate, deny, or distort reality in order to defend against feelings of anxiety and unacceptable impulses and to maintain one's self-schema.

Freudian Theory

A set of psychoanalytic theories developed by Sigmund Freud, which emphasize the importance of unconscious processes and childhood experiences in shaping personality and behavior.

Defense Mechanisms

Strategies the ego uses to disguise or transform unconscious wishes.

Ego

Within the framework of psychoanalytic theory, it's the component of one's personality that acts as an intermediary among the desires of the id, the superego, and the exigencies of reality.