alleryStart learning →What makes a quantity a state function?
AIts value depends on the path taken to reach the state
BIts value depends only on the state, not the path taken
CIts value is always positive whatever the change may be
DIts value can be measured directly for any pure substance
Answer & Solution
Correct answer: B. Its value depends only on the state, not the path taken
1. A state function is fixed by the state a system is in, whatever route brought it there.
2. Altitude on a mountain is the example given: the summit height is the same by any path.
3. Distance walked is not a state function, since a winding route is longer than a direct one.
4. Internal energy and enthalpy are state functions, while heat and work are not.
5. State functions may be positive or negative, so sign is not part of the definition.
_Source: OpenStax Chemistry (CC BY 4.0), Ch 5 "Thermochemistry", section 5.3 Enthalpy_
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