The Element X Has Two Naturally Occurring Isotopes

question 167

Multiple Choice

The element X has two naturally occurring isotopes. The masses (amu) and % abundances of the isotopes are given in the table below. The average atomic mass of the element is amu.

• A) 34.02
• B) 30.20
• C) 35.22
• D) 32.73
• E) 33.19

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Definitions:

Repression

A defense mechanism in psychoanalytic theory where unpleasant thoughts, feelings, or memories are unconsciously excluded from consciousness.

Psychological

Relating to the mind or mental processes and how these affect behavior and well-being.

Freud's Psychosexual

A theory proposed by Sigmund Freud that describes how personality develops early in life from childhood through several psychosexual stages.

Oedipus Complex

A concept in psychoanalytic theory referring to a child's unconscious sexual desire for the opposite-sex parent and jealousy toward the same-sex parent.