Rate of reaction Flashcards
Rate of reaction equations
Product made/ time
Reactant used/ time
How does surface area impact the rate of reaction?
The higher the surface area, the higher the rate of reaction
How does temperature impact the rate of reaction?
The higher the temperature, the faster the rate of reaction. This is because there is more energy
What does a catalyst do plus 2 types
It lowers the activation energy required for a reaction. The catalyst is unchanged after the reaction. A homogeneous catalyst is the same state as the reactant but a heterogeneous catalyst is a different state
How does concentration impact the rate of reaction?
It increases it because there are more collisions
How does pressure impact the rate of reaction?
It increases it because there is a higher chance of successful collisions
Strong vs weak acids
Strong acids ionise completely in water
Weak acids only see a small proportion of acid particles dissociate to release H+ ions
Ionisation of week is reversible, equilibrium between undissociated and dissociated acid
Higher concentration of H+ ions, faster rate of reaction
Ph
Measure of concentration of H+ ions in a solution
Ph decrease of 1 means 10 times more concentration of H+ ions
Lower ph, more concentrated
Strong vs concentrated acids
Strength tells us what proportion of acid molecules ionise in water
Concentration is how much acid there is in a certain volume of water (how watered down)
Reversible reactions
Will reach equilibrium where the forward and backwards reactions are the same speed
Backwards speeds up as more products are made and concentration increases
Equilibrium can only be reached in a closed system
Equilibrium to each side means
Right has more concentration of products than reactants
Left more concentration of reactants than products
Affected by:
Temperature
Pressure in gases
Concentration
Le chatelier’s principle
If you change the conditions of a reversible reaction at equilibrium the system will try to counteract it
Le chatelier temperature
Exothermic one way endothermic the other
If you decrease temp it goes to exo, more products that way and increase opposite
Le chatelier pressure
If you increase pressure the equilibrium moves to where there are fewer molecules of gas
Le chatelier concentration
Increasing concentration of reactants the system tries to counteract that by making more products and vice versa
