When 0560 G of Na(s)reacts with Excess F₂(g)to Form NaF(s), 13

question 5

Multiple Choice

When 0.560 g of Na(s) reacts with excess F₂(g) to form NaF(s) , 13.8 kJ of heat is evolved at standard-state conditions. What is the standard enthalpy of formation ( $\Delta$ H°_f) of NaF(s) ?

• A)24.8 kJ/mol
• B)570 kJ/mol
• C)-24.8 kJ/mol
• D)-7.8 kJ/mol
• E)-570 kJ/mol

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Definitions:

Generalization

A principle in psychology that refers to the tendency to apply learned responses to similar stimuli beyond the original conditions of learning.

Secondary Reinforcement

A process by which a stimulus reinforces a behavior after it becomes associated with a primary reinforcer.

Stimulus Predictability

The extent to which the occurrence and properties of a stimulus can be anticipated based on previous experience.

Spontaneous Recovery

The reappearance of a previously extinguished conditioned response after a period of no exposure to the conditioned stimulus.