The Valence Electron of a Sodium Atom Does Not Sense

question 89

Multiple Choice

The valence electron of a sodium atom does not sense the full +11 of the sodium nucleus. Why not?

• A)There are two "non-valence shell" electrons shielding the sodium nucleus from sensing it.
• B)There are two inner shells of electrons containing ten electrons shielding the sodium nucleus from sensing it.
• C)Since the +11 charge is spread evenly around the entire spherical surface of the nucleus, the actual force of the charge in any given direction is greatly diminished.
• D)The distance from the nucleus to the loosely held lone valence electron varies greatly over time. So, the average sense of charge from the nucleus is considerably less than +11.

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Definitions:

Partial Reinforcement Effect

The tendency for a response that is reinforced after some, but not all, correct responses to be very resistant to extinction.

Continuous Reinforcement

A method of learning in which a behavior is reinforced each time it is performed, leading to faster acquisition of the behavior.

Continuous Reinforcement

A reinforcement schedule in which every occurrence of the instrumental response (desired response) is followed by the reinforcer.

Fixed Interval

A schedule of reinforcement where the first response is rewarded only after a specified amount of time has elapsed, encouraging a pause after receiving the reward and a higher rate of response as the time for the next reward approaches.