Rate Graphs Flashcards
All 5 cards in this deck
On a graph of volume of gas against time, what does a flat (levelled-off) line show?
The reaction has stopped: no more gas is made because a reactant has been used up.
On a volume of gas against time graph, where is the rate of reaction fastest, and why does it slow down?
At the start, where the curve is steepest; the rate falls as reactants are used up, giving less frequent collisions.
What is the equation for the mean rate of reaction?
mean rate of reaction = amount of product formed (or reactant used) ÷ time taken
e.g. volume of gas in cm ÷ time in s gives cm s.
How is the rate at a particular time found from a curved volume–time graph?
Draw a tangent to the curve at that time and find its gradient (change in volume ÷ change in time), in cm s.
How does the curve for powdered magnesium compare with the curve for the same mass of magnesium ribbon on the same axes?
Steeper and to the left of the original curve, levelling off at the same final volume.