Thermochemistry study guide Flashcards
Exothermic
The released heat — Heat on the product sides ←
Endothermic
The absorbed heat —- Heat on the reactant sides →
System -
Specific part being studied
Surroundings
Everything else outside of that system
Systems vs. surroundings
(Ice cube demo - system was Ice Cube (Gaining heat) Surrounding Was everything around the Ice Cube)
Temperature
A measure of the average kinetic energy of the particles within a substance
Heat energy
The result of the movement of tiny particles (Atoms, molecules, or ions)
Kinetic energy
Things in motion or moving
Potential energy
The energy stored in an object substance (due to its bonds or attractions)
Temperature vs kinetic energy
Higher temperature = Higher kinetic energy.
Mass and Speed Relation
Heavier particles move more slowly at the same KE.
Specific Heat Capacity (c):
The amount of heat needed to raise 1 g of a substance by 1°C.
What happens to the temperature when you have LOW specific heat
Fast temperature change
What happens to the temperature when you have HIGH specific heat
Slow temperature change
Specific heat
how slowly or quickly heat can change temperature
Objects at the same temp have the same….
KE`
Lighter objects move….
Heavier objects move….
Faster
Slower
Low specific heat
less energy to change temperature, heat up and cool down quickly
High specific heat
More energy to change temperature, heat up and cool down slowly
Calorimetry Problems:
Heat lost by one object = Heat gained by another.
Parts of a phase diagram
Sloped Lines:
Flat Lines:
- Temperature change (q=mc∆T applies).
- Phase change (q=m∆H
If heat is in the reactant: Endo or exo
Endothermic
- melting or vaporizing
If heat is in the product:
Endo or exo
- Exothermic
—- Condensation, freezing
Solid to Liquid to Gas:
Particles gain energy, move faster, and become less ordered.
Gas to Liquid to Solid:
Particles lose energy, move more slowly, and become more ordered.
