C10 - Rates and Equilibria Flashcards
what are reversible reactions
when the products of the solution can react together and reform the original reactants
what is the forward reaction called
endothermic
what is the reverse reaction called
exothermic
what is equilibrium
the point in a reaction where the rate of the forwards reaction and the reverse reaction are the same
what is Le Chateliers Principle
when a reaction at equilibrium is changed, it will shift the position of the equilibrium to oppose that change
what is the effect of changing the pressure on equilibrium
if the pressure is increaed the position of the equilibrium shifts in the direction of fewer molecues of gas
what is a catalyst
increases the rate of reaction by lowering the activation energy and providing an alternative pathway for the reaction withut being used up
what is a reactant
a chemical substance that is present at the start of a chemical reaction, and is changed as the chemical reaction proceeds
what is a product
a substance that is present at the end of a chemical reaction
what is a dynamic equilibrium
the point in a reaction where the rate of the forwards reaction is equal to the rate of the revserse reaction
only can occur in a closed system where none of the reactants or products can escape
experiment: what happens to copper sulfate when heated
what happens when adding water
- the blue crystals turned into white crystals
- by adding water the white crystals returned to back to its original colour of blue
experiment: what happens to hydrated cobalt chloride when heated
what happens when adding water
- started as pink cobalt chloride, when heated it went blue
- water returns it back to its original colour (pink)
what is a salt
a substance formed when a metal or non-metal base reacts with an acid
what is it meant by water of crystalisation
water that is trapped withtin the crystal structure
what is a hydrated salt
solid crystals contain water of crystalisation
what is an anhydrous salt
contains no water of crystalisation
what is a rate
The rate of a reaction is how quickly the reactants turn
into the products.
how do you calculate rate
rate = change in the mass/
time taken
what factors can affect the rate
- increasing the temperature
- increasing the concentration of the solutions
- increasing the pressure of gases
- increasing the rurface area of solids
what is the rate of a reaction
how quickly reactants are used up or products are produced
what is the unit for rate of a reaction in an reaction involving change in mass
g/s
what is the unit for rate of a reaction in an reaction involving change in volume
cm3/s
what are the three reaction conditions that can be changed
- concentration
- temperature
- pressure
