Topic #6: The Rate and Extent of Chemical Change Flashcards Preview

Chemistry > Topic #6: The Rate and Extent of Chemical Change > Flashcards

Flashcards in Topic #6: The Rate and Extent of Chemical Change Deck (13):
1

What are the two equations for calculating rate of reaction?

Quantity of product formed / Time taken
Quantity of reactant used / Time taken

2

How do we calculate the mean rate of reaction at a certain point?

Draw a tangent of the graph, then do difference in y / difference in x

3

What are the 5 things that affect the rate of reaction, and how so?

Temperature - the higher the temperature, the higher the rate
Concentration of reactants - increased concentration - increased rate
Catalysts - Catalysts speed up reactions
Pressure of the gases - higher pressure, higher rate
Surface area - larger surface area, increased rate

4

What is the collision theory for activation energy?

Reactions can only begin when enough particles collide with sufficient energy

5

How do catalysts speed up reactions?

They reduce the amount of energy that is needed to start the reaction

6

Are they used up in reactions?

No

7

What does the reversible reaction arrow look like?

Half an arrow point left, half pointing right, on top of each other

8

When reactions are reversed is their endo/exo-thermic trait reversed too?

Yes

9

What is equilibrium?

When the forward and backwards happen at the same time (no products or reactants are escaping)

10

What is Le Chatilier's Principle?

That when a system changes, a anew equilibrium will be reached

11

How does changing concentration affect the equilibrium?

Increase - more product
Decrease - less product

12

How does temperature affect the equilibrium?

increased - products increase for an endothermic reaction, products decrease for an exothermic reaction.

decreased - products decrease for an endothermic reaction, products increase for an exothermic reaction

13

How does a pressure change affect the equilibrium?

increase - equilibrium shifts towards side with smaller molecules

decrease - equilibrium shifts towards the side with larger molecules