Unit 3 - Calculations Flashcards
Controlling the rate, Getting the most from reactants, Chemical Energy, Equilibrium, and Chemical Analysis
Explain the ‘Collision Theory’?
For particles to react, they must collide, the collision geometry must be correct, and the particles must have enough energy to overcome the activation energy
Define, ‘Activation Energy’?
The minimum kinetic energy required for a reaction to occur
What factor(s) affect the rate of reaction?
Concentration, Particle size, Temperature, and Pressure
“As the concentration increases, there are more reactant particles, which _________ the number of collisions”
As the concentration increases, there are more reactant particles, which increases the number of collisions”
“As the particle size decreases, the surface area increases, which _________ the number of collisions”
As the particle size decreases, the surface area increases, which increases the number of collisions
“As the temperature increases, the particles move faster, which ________ the number of collisions”
“As the temperature increases, the particles move faster, which increases the number of collisions”
“As the pressure increases, the particles are closer together, which _________ the number of collisions”
“As the pressure increases, the particles are closer together, which increases the number of collisions”
Explain what Catalysts do in reactions?
They speed up chemical reactions by decreasing the activation energy, and therefore provide an alternative pathway for the reaction to occur
When is the ‘Relative rate calculation’ useful?
It’s useful in reactions where a colour change can be used to indicate the end of the reaction
Define, ‘Enthalpy’?
The change in potential energy
“The enthalpy change for an exothermic reaction is ________”
“The enthalpy change for an exothermic reaction is negative”
“The enthalpy change for an endothermic reaction is ________”
“The enthalpy change for an endothermic reaction is positive”
Define, ‘Activated Complex’?
The unstable arrangement of atoms formed at the maximum of the potential energy barrier during a reaction
Define, ‘Chromatography’?
A technique used to separate the components present within a mixture
