Which of the Following Observations Is/are Examples of Chemical Change $^{\circ}$

question 3

Multiple Choice

Which of the following observations is/are examples of chemical change?
1) Iron (Fe) rusts,forming Fe₂O₃.
2) The density of water increases when it changes from a solid to a liquid.
3) Sodium chloride melts at 801 $^{\circ}$ C.

• A) 1 only
• B) 2 only
• C) 3 only
• D) 1 and 2
• E) 2 and 3

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Definitions:

Classical Conditioning

An instructional approach where repetitively linking two stimuli causes a reaction, at first prompted by the second stimulus, to be elicited by the first stimulus over time.

Imprinting

A form of learning occurring at a particular life stage that is rapid and apparently independent of the outcomes of behavior.

Operant Conditioning

A learning process by which the strength of a behavior is modified by reinforcement or punishment.

Classical Conditioning

The process of acquiring knowledge through the repeated combination of two stimuli, where a response initially caused by the second stimulus is ultimately caused by the first stimulus alone.