Internal energy
6 flashcards to master this topic
Define 'internal energy' of a system.
Internal energy (U) is the total kinetic and potential energy of all the molecules within a system. It is a state function, meaning it only depends on the current state of the system, not how it reached that state.
What two forms of energy contribute to the internal energy of a system?
Internal energy is the sum of the random distribution of kinetic energies (due to molecular motion) and potential energies (due to intermolecular forces) of the molecules within the system.
How does the temperature of an object relate to its internal energy?
An increase in the temperature of an object corresponds to an increase in its internal energy, specifically the kinetic energy component. Higher temperature means faster average molecular motion.
Does internal energy depend on the path taken to reach a particular state?
No, internal energy is a state function. This means the internal energy of a system depends only on its current state (temperature, pressure, volume, etc.) and not on the process or path taken to reach that state.
Describe the relationship between heat transfer to a system and its internal energy, assuming no work is done.
When heat is transferred to a system and no work is done (
Why is the motion of molecules considered 'random' when discussing internal energy?
The motion is random because individual molecules move in all different directions and with a variety of speeds. This randomness means we consider average kinetic energy when assessing the internal energy.
Ready to test yourself?
Practice with MCQ questions to check your understanding of Internal energy.
Take QuizStudy Mode
Rate each card Hard, Okay, or Easy after flipping.