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Thermochemistry - Coggle Diagram
Thermochemistry
Internal Energy
Energy associated with the random disordered motion of molecules
Is talking about th invisible energy on the atomic and molecular scale
Is separated in scale from the macroscopic ordered energy associated with moving objects
Kinetic energy
Transtational
Monoatomic gases
1 type of energy
Rotational and Vibrational
Polyatomic gases
2 types of energy
System and surroundings
System
Refers to the chemical reaction that is taking place
Surroundings
Refers to everything else in the universe
Chemical reactions
Exothermic
The heat is transferred from the system to the surroundings (surroundings get hotter)
Endothermic
The system takes in heat energy from the surroundings (surroundings get cooler)
Enthalpy changes
The enthalpy change is the amount of heat energy taken in/given out in a chemical reaction.
the symbol for enthalpy is "H" and for enthalpy changes is "ΔH"
ΔH for an exothermic reaction will always be negative
ΔH for an endothermic reaction will always be positive
Measuring energy
Heat
Thermal energy transferred from a hotter system to a cooler system that are in contact.
We are talking about a process
Temperature
Measure of the average kinetic energy the atoms or molecules in the system
We are referring to a mesuareg of the amount of energy of a certain object
You need to use an instrument
Potencial energy
Associated with the intermolecular attractive forces
International forces
Dipole-dipole force
Ion-dipole force
Interaction between ions and polar molecules
Is the attraction and repulsion between molecules
Hydrogen bonds
Is a type of dipole-dipole interaction
But is between molecules that have a hydrogen atom and a very electronegative atom
London force
Basic force
Is present in all interactions
When the repulsion takes place the molecules move the other way to avoid repulsion. Polar molecules are created. Finally atraction takeas place.
When 2 metals (non-metal) approach the electronic are going to REPEL.
<--- Far apart --->
1 more item...
liquids or solids
