2.4 Rates Flashcards
2 ways to work out the rate of a chemical reaction?
- We can find out how quickly the reactants are used up as they make products.
- We can find out how quickly the products of the reaction are made.
What are three types of measurement which can be made to monitor the rate of a chemical reaction?
- Measuring the decreasing mass of a reaction mixture.
- Measuring the increasing volume of gas given off.
- Measuring the decreasing light passing through a solution.
Rate of reaction=?
Amount of reactant used or amount of product formed/ time
4 main factors which affect rate of a chemical reaction…
Surface area
Temperature
Presence of a catalyst
Concentration of solutions OR pressure of gases
What are 2 things that must happen between two reacting particles?
They must collide and react with sufficient amount of energy( activation energy) 👈 COLLISION THEORY
When do reaction rates increase?
When collisions are more energetic and frequent.
What variable do you put on the y axis?
Dependent variable
What variable do you put on the x axis?
Independent variable
10 degrees Celsius temperature increase👈 what does this do?
Roughly doubles the reaction rate
When are reaction usually at their fastest?
When the reactants first meet. (Start of the reaction)
Why do concentrated solutions react more quickly?
Because there are more particles in the same volume of water e.t.c.
A catalyst
A substance which increases the rate of a reaction.
What types of chemicals are often used as catalysts?
Transition metals (often used in industry)
How do catalysts increase reaction rate?
Lowers the activation energy needed by the particles to react by providing a different pathway for the reaction to proceed so now more particles will have the minimum energy required, so the rate is increased.
In which industrial process is the catalyst nickel used?
Hydrogenation of sunflower oil
