C6 - Rates of Reaction Flashcards
What must happen to the particles if a reaction is going to take place?
They must collide with enough energy
Which of the lines on this rate of reaction graph would have happened at the lowest temperature?
C - The less steep the line, the slower the reaction
The lower the temperature the slower the reaction
Which of the lines on this rate of reaction graph represents a COLDER reaction
C - Colder reactions happen slowly
(the particles have less energy, so they move slowely and collide less frequently)
The less steep the line, the slower the reaction
Where on this graph does the reaction finish?
Where the line goes flat
Which of the lines on this rate of reaction graph shows the SLOWEST reaction?
C - The less steep the line, the slower the reaction
Which of the lines on this rate of reaction graph shows the FASTEST reaction?
A - The Steepest lines show the fastest reactions
Give 2 ways you can measure the rate of reaction which releases a gas
Use a gas syringe to collect and measure the volume of gas
Measure the mass loss
What factors can affect the rate of a reaction?
1) Temperature
2) Concentration / Pressure
3) Surface Area
4) Adding a catalyst
Explain how increasing the temperature affects the rate of a reaction
(try to use the words energy / speed / frequency / Energy / collision)
- Increasing the temperature increases the energy
- So particles move faster
- And collide more frequently
- with enough energy
Explain how increasing the concentration affects the rate of a reaction
(try to use the words particles / frequency / collision)
- When the concentration increases there are more particles in a given area
- This means they collide more frequently
What does a catalyst do?
Lowers the activation energy
Gives the reaction an alternative pathway to happen on
How can you measure the rate of a reaciton that produces a solid?
A solid can make the reaction go cloudy
Draw a cross under the reaction and time how long it takes for the cross to disapear
What is a reversible reaction?
Draw the symbol we use to represent a reversible reaction
A chemical reaction which will break back down into the reactants
Required Practical – A student used this equipment to investigate how changing the concentration of acid affects the rate of reaction
What is the Independent Variable (changed)
What is the dependent Variable (measured)
What are the Control Variables (keep the same)
IV - Concentration of acid
DV - Amount of gas produced
CV - Mass/Volume of reactants
Temperature
Required Practical – A student used this equipment to investigate how changing the TEMPERARURE of an acid affects the rate of a reaction
IV (changed) =
DV (measured) =
CV (keep the same) =
IV (changed) = Temperature
DV (measured) = Time taken for cross to disappear
CV (keep the same) = Volume of reactants
