Rate Of Reaction Flashcards
What is the limiting reactant
The reactant that becomes used up in a reaction
With more particles of the reactant, there is more reaction and more product particles are produced
How can you increase the amount of product
Increase the reactant amount
In a reaction where gas is made how can you follow the progress of the reaction
Recording mass lost as gas escapes or by measuring the volume of the gas
Rates of reactions can be plotted
How do we show how much product was made
Drawing a horizontal line from the highest point on the graph to the
y-axis
Rates of reactions can be plotted
How do we show how long it takes to make the products
Drawing a vertical line from the start of the flat line on the graph (that indicates the reaction has finished) down to the x-axis
Rates of reactions can be plotted
How do we show which reaction is quickest on a graph
Compare steepness
Steeper the line the quicker the reaction occured
What is rate of reaction
How much product is made each second
What is the relation between collisions and reaction speed
The more particle collisions there are the faster the reaction
What is the effect of reactant temperature on reaction rate and what is happening
A LOWER temperature gives lower rate of reaction
Particles move slowly, collide less frequently with less energy, low kinetic energy. Fewer successful collisions per second
A HIGHER temperature gives higher rate of reaction
Particles move quickly,collide more often with more energy, high kinetic energy. More successful collisions per second
What is the effect of reactant concentration (or pressure of gas) on rate of reaction and what is happening
LOWER concentration gives lower rate of reaction
Particles more spread out so collide less frequently, resulting in fewer successful collisions per second
HIGHER concentration gives higher rate of reaction
particles crowded and collide often, more successful collisions per sec
What is the relation between energetic particles and success
When a collision has more energy, the chance of it causing a successful collision is increased
Why do powdered solids react faster than large lumps of the same reactant
The powder has larger surface area so more particles are available on the surface for the other reactants to collide with
There is greater chance of them colliding wich increases the reaction
More frequent collisions means a faster reaction
What is an explosion
A very fast reaction where huge volumes of gas are made
Why is it important that factories handle powders carefully
Dust (small particles, greater rate of reaction) from materials can mix with air and may cause an explosion if there is a spark
They ensure there are no sparks
What is a catalyst
When are they most effective (surface area)
A substance that increases rate of reaction and is unchanged at the end of the reaction
Small catalyst amounts speed up reaction of large amounts of reactant
They most effective when they have a large surface area with more particles exposed so collisions per second increases
