Chemistry Energy Definitions
Endothermic
System absorbs energy, energy flows into the system, reactants have lower potential energy than the products, increases the potential energy of the system, and heat absorbed is converted to potential energy.
Exothermic
System releases heat to the surroundings, energy flows out of the system, reactants have more potential energy than the products, lowers the potential energy of the system, and potential energy stored in bonds is converted to thermal energy via heat.
Joule
The SI unit of energy.
Energy
The ability to do work or produce heat.
Specific Heat Capacity
The amount of energy required to change the temperature of one gram of a substance by one degree.
Second Law of Thermodynamics
The entropy of the universe is always increasing.
1st Law of Thermodynamics
The law of conservation of energy. (The energy of the universe is constant.)
Thermal Heat
The result of random motion of the components of an object.
Thermodynamics
The study of energy.
Internal Energy (E)
The sum of all the kinetic and potential energy particles in the system and can be changed by work and/or heat.
Global Warming
The theory that explains the effect of higher greenhouse gases on our Earth's average temperatures.
Potential and Kinetic Energy
The two main types of energy.
q
Symbol for heat.
w
Symbol for work.
Entropy
A measure of disorder and randomness.
Temperature
A measure of the random motion of the components or the thermal energy.
Pyrolytic Cracking
A process developed to break apart the larger petroleum based molecules by heating them to about 700 degrees celsius. The result is more valuable smaller molecules.
State Function
A property of the system that changes independently of its pathway.
Enthalpy
A state function. The flow of energy associated with a chemical reaction.
Calorie
1000 calories. 1 kcal.
Heat
A flow of energy due to a temperature difference. The flow of thermal energy moving from high concentration to low concentration.
calorie
Amount of energy required to raise the temperature of one gram of water by one Celsius degree.
Law of Conservation of Energy
Energy can be converted from one form to another but can neither be created nor destroyed.
Potential Energy
Energy due to position or composition.
Kinetic Energy
Energy due to the motion of the object.
The Surroundings
Everything else in the universe that is not the system.
Work
Force acting over a distance.
Energy Spread
In a given process, energy is dispersed widely. Increase in the energy of the molecules in the surroundings.
Calorimeter
Is used to measure the heats of reaction.
Matter Spread
Molecules of a substance are spread out and occupy a larger volume.
Heat Death
Occurs when all then energy is spread evenly over the Earth's surface. Work will no longer be possible.
The System
Part of the universe on which we are focusing. May be exothermic or endothermic.
First Law of Thermodynamics
Same as the Law of Conservation of Energy.
Greenhouse Effect
Some of the energy from the sun is trapped by the gasses in our atmosphere and moderates the Earth's temperature.