Which of the Following Has the Smallest Radius

question 72

Multiple Choice

Which of the following has the smallest radius?

• A) Yb³⁺
• B) Ho³⁺
• C) Nd³⁺
• D) Gd³⁺
• E) Ce³⁺

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Definitions:

Unconditioned Stimulus

A stimulus that naturally triggers a response without the need for prior learning.

Counterconditioning

A therapeutic process aimed at reversing the negative effects of a conditioned response by introducing a new, positive stimulus.

Learned Response

A behavior or reaction acquired or modified by the association of a stimulus and a response.

Apparent Extinction

A situation where a species appears to be extinct based on the lack of observed individuals, but may still have surviving members in unobserved areas.