6 Rates H only Flashcards
What is the rate of a chemical reaction in terms of reactants?
How quickly the reactants in a reaction are used up
What is the rate of a chemical reaction in terms of products?
How quickly the products in a reaction are formed
What is the formula for a mean rate of reaction in terms of reactants?
quantity of reactant used/time taken
What is the formula for a mean rate of reaction in terms of products?
quantity of reactant product formed/time taken
How can you measure the quantity of a reactant or product?
In grams or in cm3
What are the two possible units for rate of reaction?
g/s or cm3/s (where s is seconds)
How could you measure the rate of a reaction from a graph?
Draw a tangent to the curve and calculate the gradient.
What is “collision theory”?
The theory that chemical reactions only occur when particles collide with sufficient energy
What factors can affect the rate of a reaction?
Temperature, surface area of a solid, concentration or reactants in solution, pressure of gases
State the effect of increasing the surface area on the rate of a reaction
Increases the rate
Explain why increasing the surface area increases the rate of a reaction
More particles are available to collide, there are therefore more frequent collisions between reactants.
State the effect of increasing the concentration on the rate of reaction
Increases
Explain why increasing the concentration increases the rate of reaction
More concentrated means more particles in solution, therefore more frequent collisions between reactants.
State the effect on increasing the pressure of a gas on the rate of reaction
Increases
Explain why increasing the pressure of a gas increases the rate of a reaction
Less space for the particles to move around in, therefore more frequent collisions