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, ‘Exothermic’?
A reaction that releases heat energy
Define, ‘Endothermic’?
A reaction that takes in energy
Define, ‘Activation Energy’?
The minimum kinetic energy required for a reaction to occur
Define, ‘Temperature’?
A measure of the average kinetic energy of the particles in a substance
What factor(s) affect the rate of reaction?
Concentration, Particle size, Temperature, and Pressure
“As the concentration increases, there are ____ ________ ________, which increases 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 _______ ____ _________, which increases the number of collisions”
As the particle size decreases, the surface area increases, which increases the number of collisions
“As the temperature increases, the _________ ____ ______ due to an increase in energy, which increases the number of collisions”
“As the temperature increases, the particles move faster due to an increase in energy, which increases the number of collisions”
“As the pressure increases, the particles are ______ ________, which increases 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
What effect do Catalysts have on the Enthalpy change of an reaction?
No effect
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’?
A measure of the chemical energy in a substance
“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
What factors influence industrial process designs?
Availability, Recycling, Energy requirements, Marketability of by-products, and Product yield
What environmental considerations are included in the process designs?
Minimising waste, Avoiding the use or production of toxic substances, and Designing products which will biodegrade
What does the addition of a Catalyst do to the position of the equilibrium?
It increases the rate of the forward and the reverse reaction equally but does not affect the position of equilibrium
Define, ‘Concordant’?
Titre volumes that are within 0.2 cm3 of each other
Define, ‘Standard solutions’?
Solutions of an accurately known concentration
Define, ‘Dynamic Equilibrium’?
The rate of the forward reaction equals that of the backward reaction
