Rates Of Reaction And Energy Changes Flashcards
How can you measure the rate of reaction?
It can be observed even by measuring how quickly the reactants are you stop or how quickly the products are formed.
How can you find rate of reaction?
Divide the amount of reactant used all the amount of product formed by the time
Describe the precipitation method used to measure the rate of reaction…
This method works for any reaction when mixing to see three solutions produces a precipitant which cloud is the solution. Firstly you mix the two reactant solutions and put the flask on a piece of paper that has a mark on it. Observe the mark for the mixture and measure how long it takes for the mark to be on unscene. The faster it disappears, the faster the reaction
Describe the experiment used to measure reaction rates about the change in mass
You can measure the rate of reaction that produces a gas using a mass balance. As the gas is released the loss mass is easily measured on the balance. The quicker the reading on the balance drops the faster the reaction. You know the reaction is finished with the reading on the balance stop changing. You can use your results to plot a graph of change in mass against time.
How can you measure the rate of reaction by the amount of volume of gas given off?
This involves the use of a gas syringe to measure the volume of gas given off. The more gas given off during a time interval the faster the reaction. You can tell the reaction is finished when no more gas is produced. You can use your results to plot a graph of gas volume against gas time elapsed.
Finer particles of solid means…
A higher rate of reaction
What does the rate of reaction depend on?
Temperature concentration or pressure( p for gases)brackets and the size of particles (for solids)
Reaction rate to explain by collision theory. It’s simple really. The rate of chemical reactions depends on…
The collision frequency of reacting particles. The more successful collisions are are the faster the reaction is. The energy transferred during a collision the minimal energy that particles need to react when they collide is called the activation energy particles need to collide with at least the activation energy for collision to be successful
What is activation energy?
The minimum amount of energy needed for once to break in a reaction to start
How do you catalysts work?
My decreasing the activation energy needed for the reaction to occur.
They do this by providing an alternative reaction pathway that has a lower activation energy. As a result more of the particles have at least a minimum amount of energy needed for a reaction to occur in the particles collide
What is an exothermic reaction?
A reaction which gives out energy to the surroundings
What is an endothermic reaction?
Reaction which takes in energy from the surroundings
How do I calculate the overall energy change?
Energy required to break bonds subtract energy released by forming bonds
