Top 6 - The Rate and Extent of Chemical Change Flashcards
On a rate of reaction graph, what does the line getting steeper show?
It shows that the reaction is getting faster.
What does a flat line on a graph of amount of products against time show?
Flat lines show that the reaction has finished.
What are the four factors that affect the rate of a chemical reaction?
Temperature
Concentration of solution
Surface Area
Presence of a catalyst
What is a catalyst?
A catalyst is a substance that speeds up a reaction without being used up
State the equation that could be used to calculate the mean rate of a reaction.
Rate of Reaction =
Amount of reactant used or amount of product formed
———————————————
Time
What is a precipitate
A precipitate can cause (a substance) to be deposited in solid form from a solution
Explain why measuring a mass change during a reaction is an accurate method of measure rate.
Because if you take measurements at regular intervals, you can spot the rate of reaction graph and find the rate easily.
What is a tangent? And what does it do?
A tangent is a straight line that touches the curve at one point and doesn’t cross it. And measures the rate of reaction at a specific point of a rate of reaction graph.
Using the equation show how you would use a tangent to find the gradient of a curve at a particular point.
(Change in y)
——————- = gradient of tangent (g/min)
(Change in x)
Which of the following statements is true?
A) In a reaction at equilibrium, there is the same amount of products as reactants.
B) If the forward reaction in a reversible reaction is exothermic, then the reverse reaction is endothermic
C) If the equilibrium of a system lies to the right, then the concentration of products is less than the conc. of reactants.
A
What affect will decreasing the temperature have on a reversible reaction in which the forward reaction is exothermic?
It will decrease the rate of the backwards endothermic reaction. You will also get more products for the exothermic and fewer from the endothermic.
What will happen when you raise the temperature in an equilibrium reaction?
The equilibrium will favour the endothermic direction to try and decrease the temperature.
What will happen when you lower the temperature in an equilibrium reaction?
The equilibrium will favour the exothermic direction to try and decrease the temperature.
