1.1 Rates & Reaction Pathways Flashcards
Formula for Average Rate?
Rate = △Quantity
—————
△Time
Formula for Relative Rate?
Rate = 1
——-
Time
What are the 2 circumstances for a reaction to occur?
- Collisions must have sufficient energy
- Collisions must occur with the correct orientation
Name 4 factors affecting the rate of a reaction
Particle Size
Concentration
Pressure
Temperature
Catalyst
Describe how Particle Size affects the rate of reaction
The smaller the particles, the faster the reaction as smaller particles provide a larger surface area
Describe how Concentration affects the rate of reaction
The higher the concentration, the faster the reaction as the higher concentration has more particles in a given volume
Describe how Pressure affects the rate of reaction
Increasing pressure will make the reaction faster
Describe how Temperature affects the rate of reaction
Temperature is a measure of the overall kinetic energy in all the particles in a substance
Increasing the temperature leads to more collisions
Describe how Catalysts affect the rate of reaction
They speed up the reaction while taking an alternate pathway and lower the activation energy
What is Enthalpy
Enthalpy is the chemical energy in a substance
What is the formula for calculating Enthalpy?
△H = P - R
Describe an Exothermic Reaction
Heat energy is released to the surroundings
△H is always negative
Describe an Endothermic Reaction
Heat energy is absorbed from surroundings
△H is always positive
Describe the Activation Energy
The Activation Energy is the minimum energy required for a collision to be successful
Describe the Activated Complex
The Activated Complex is an unstable group of atoms formed at the maximum potential energy barrier
