Thermodynamics Flashcards
What is energy?
The ability to cause change
What is “work”?
The change that requires energy
What is the first law of thermodynamics?
Energy cannot be created or destroyed
- energy can change locations
- energy can change forms
- all energy that enters/leaves the system came from the surroundings
What is potential energy?
Energy that is stored due its position or chemical structure (energy at rest)
What is kinetic energy?
Energy that is in motion/change
Is there potential energy in the nucleus? Why or why not?
The nucleus has zero potential energy. Electrons with more potential energy move to higher energy levels. Whereas electrons with low potential energy are near the nucleus
What type of molecules have more potential energy?
Non-polar molecules with a lot of covalent bonds
- an electronegativity under 0.4 means non-polar in this course
Is there potential energy at equilibrium?
Yes but it is very low
What is enthalpy
The sum of kinetic and potential energy in molecules
Does work change the enthalpy of a system?
Yes
What is exothermic?
Heat is released into the surroundings. Reactants have more enthalpy than products
What is endothermic?
Heat is absorbed into the surroundings. Reactants have lower enthalpy than products
What are some “current conditions”?
- Temperature, pH, atmospheric pressure (constant in a cell)
- [reactants], [products] (cells manipulate those a lot)
What are spontaneous reactions?
Reactions that can happen under “current conditions”
Does spontaneous mean instantaneous?
NO