Topic C6- The Rate And Extent Of Chemical Change Flashcards
What is the equation for rate of reaction?
Amount of reactant used or amount of product formed(cm^3 or g) / Time(s)
How do you test for the rate of reaction with colour change?
You can observe a mark through the solution and measure how long it takes for it to disappear- the faster the mark disappears, the quicker the reaction
You can also measure lose or gain of the solutions coulour
How do you test for the rate of reaction with change in mass?
As the gas is released, the mass disappearing is measured on the balance- the quicker the reading on the balance drops, the faster the reaction
How do you test for the rate of reaction with the volume of gas given off?
By using a gas syringe to measure the volume of gas given off- the more gas given off during a given time interval, the faster the reaction
What does increasing the temperature do to the rate of reaction?
The particles will move faster, meaning they will collide more frequently
What does increasing the concentration or pressure do to the rate of reaction?
There are more particles colliding about in the same volume, so there are more frequent collisions between the reactant particles
What does increasing the surface area do to the rate of reaction?
Smaller pieces will increase its surface area to volume ratio, so the particles around it will have more area to work on, meaning more frequent collisions
How does using a catalyst increase the rate of reaction?
They provide an alternative reaction pathway with a lower activation energy, which speeds up the reaction
How do you calculate the mean rate of reaction from a graph?
Change in y / Change in x
How do you find the reaction rate at a particular point on a graph?
Draw a tangent then do
Change in y / Change in x
What is the equilibrium?
When the forward reaction goes at exactly the same rate as the backward one
What happens to the reactions at equilibrium?
The concentrations of reactants and products have reached a balance and won’t change
If the equilibrium lies to the right what happens to the concentration of products?
The concentration of products is greater than that of the reactants
What 3 conditions does the position of equilibrium depend on?
Temperature
Pressure(only gases)
Concentration
In reversible reactions, if the reaction is endothermic in one direction then what is the other?
Exothermic
