TOPIC C6 THE RATE AND EXTENT OF CHEMICAL CHANGE Flashcards
what is the rate of reaction
how fast the reactants are changed into products
how to use a graph to understand the rate of reactions
-steeper the line, the faster the rate of reaction
-overtime line becomes less steep as the reactants are used up
-Quickest reactions have STEEPEST lines and become flat in the least time
what factors relate to the collisons between particlles influence the rate of reacction
- collision frequency of reacting particles, the more collisions the faster the reaction is
- energy transferred during a colison, particles have to collide with enough energy for collisions to be successful
state 4factors affecting rates of reaction
- temperature
- concentration of a solution
- surface area
- presence of a catalyst
why does increasing the temperature increase the rate of reaction
-when temperature is increased all particles move faster
-when moving faster, they collide more frequently
-faster they move, the more energy they have so more collisions will have enough energy
how does increase in concentration or pressure increase rate
-if a solutions more concentrated, it means there are more particles knocking about in the same volume
how does surface area affect rate
-if 1 reactant is a solid, then breaking it up into smaller pieces will increase its surface area to volume ratio
-means the same volume of solid, particles have more area to work on
-more frequent collisions
how do you calculate mean rate from a graph
-work out overall change in y value and then divide this by total time tkaen
how does using a catalyst affect rate
-speeds up reactions
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what is a tangent
-a straight line that touches a curve at a particular point without crossing it
how to pick a tangent
- position ruler where you need to find the rate
- adjust ruler until the space between the ruler and the curve is equal on both sides
- draw a line along the ruler to make the tangent
- pick 2 points on the line and use them to calculate the graf
