Topic 4- Lecture 15 Flashcards
A form of energy measured in J
Heat
Measure of the average KE of atoms and molecules in a system
Temperature
KE increases as…
Temperature and velocity increase
Distribution of KEs ___________ as temperature increases
Increases
Two systems at different temperature that are in ___________________ with one another will ______________________.
Thermal contact
Exchange energy/ heat
Transferred from high to low
Temperature
Energy
Same temp
Thermal equilibrium
Conservation of energy
Energy cannot be created or destroyed, but can be transformed from one form to another
System
Actual chemical reaction that is taking place
Surroundings
Anything other than the system
Change in a systems internal energy
ΔE= q+w ΔE= E final- E initial Change in energy Heat that is transferred Work done on the system by surroundings
In an isolated system, energy is_____________
Conserved
Endothermic reaction
Heat goes into system, feels cold
Ectothermic reaction
Heat leaves the system, feels hot
Work equation
w= -PΔV
Work
Negative pressure
Change in volume
Work endothermic process
Collisions increase
Concentration increases
Volume decreases
Pressure increases
Work exothermic process
Collisions decrease
Concentration decreases
Collisions decrease
Pressure decreases
Enthalpy
Heat that is released or absorbed in a chemical reaction
ΔH
Enthalpy equations
ΔH= H products- H reactants ΔH= ΣBE (bonds broken) - ΣBE (bonds formed)
Energy is always ______________ during the FORMATION of a bond
Released
The same amount of energy must be _____________ to break that specific bond
Added/ absorbed
More energy released during the formation of the bonds than required to break the reactants
Exothermic
-
Less energy released during the formation of the bonds than required to break the bonds of reactants
Endothermic
+
Lewis dot structures when calculating ΔH
Reactants - products
Thermodynamics is the…
Relationship between chemical reactions and heat
