Topic 8 - Rates of Reaction and Energy Change (Year 11) Flashcards
What are the three ways of collecting rate of reaction data?
Measuring decreasing mass, Measuring volume of gas given off and measuring light passing through a solution.
When measuring the rate of reaction using a balance, how do you know the reaction has finished?
The mass will stay constant
When measuring the rate of reaction using a gas syringe, how do you know the reaction has finished?
The volume of gas will stay constant.
A measuring cylindar can be used to measure the rates of reaction in an experiment. What piece of equipment can also be used to measure the gas from an experimennt?
Gas syringe
What is the equation used to to calculate the rate of reaction?
Mean rate of reaction = volume of reactant used/product formed ➗ time taken
An experiment is being carried out into the rate of reaction of an experiment using a mass balance. The reaction gives off a harmful gas. Apart from wearing gloves, lab coat and safety glasses what other safety precautions could be taken?
Carry out the the experiment in a fume hood.
Sodium thiosulfate and hydrochloric acid solutions are both clear, colourless solutions. When added together, they react to form a yellow precipitate. Breifly outline a method that you could use to investigate this rate of reaction.
Draw a cross ona piece of paper and place under a conical flask. Add the reactants into the conical flask and start the stopwatch. Record the time taken for the cross to dissapear by the precipitate.
When sodium carbonate is added to hydrochloric acid, a gas is released. Breigly outine a method you could use to investigate this rate of reaction.
Add the acid into a concial flask that is attached to a gas syringe. Add the marble chips. Collect the gas given off and measure the volume at given time points.
What are the five different ways of speeding up the rate of reaction?
Temperature, Concentration, Surface area, Pressure, Catalyst
How will increasing temperature affect rate of reaction? Explain why.
Particals have more energy, they move faster and therefore have more chance of colliding. When they do collide they collide with more energy, meaning ha higher chance of a reactin. This will increase the rate of reaction.
How will increasing pressure affect rate of reaction of gases? Explain why.
Increasing pressure, means the same number of particles in a smaller volume. This means particles are more likely to collide, more likely to react and increase the rate of reaction.
How will increasing sureface area affect rate of reaction? Explain why.
Increasing surface area increases the area in which particles can collide. This means particles are more likely to collide, more likely to react and increase the rate of reaction.
How will increasing concentration affect rate of reaction? Explain why.
Increasing particles, increases the number of particles in a given volume. This means particles are more likely to collide, more likely to react and increase the rate of reaction.
How will decreasing temperature affect rate of reaction? Explain why.
Decreasing temperature, particles have less energy. This means that they move slower, meaning fewer chances of collisions, when they do collide they have less energy and less likely to react.
How will decreasing pressure affect rate of reaction? Explain why.
Decreasing pressure, same number of particles in more space. This means particles are less likely to collide and decreases the rate of reaction.
How will decreasing sureface area affect rate of reaction? Explain why.
Decreasing surface area, less area for the particles to collide with the reactant. This means particles are less likely to collide and decreases the rate of reaction.
How will idecreasing concentration affect rate of reaction? Explain why.
Decreasing concentration, same number of particles in more volume.This means particles are less likely to collide and decreases the rate of reaction.
Explain how a catallyst works.
Increases the rate of reaction, by decreasing the activation energy. A catalyst doesn’t get used up in a reaction.
How could you increase the surface area of a 5g marble chip?
By breaking the marble chip up into smaller pieces.
When the line on a rate of reaction graph goes flat, what does this tell you about the reation at that point?
When the line goes flat it means that the reaction has finished - no more gas is being produced.
What product of the sodium thiosulfate and hydrochloric acid reaction cause the solution to go colourless?
Solid sulfur is produced in a precipitation reaction, causing the solutin to turn a yellow colour
