CHEMISTRY TOPIC 6

• what can the rate of reaction be measued by

  using the amount of product used or the quantity of prodcut formed over time
• what is the rate of a chemical reaction?

  its hows fast the reactants are changed into products
• the rate of reaction can be measured by

  how fast the reactants are being used and how fast the products are being formed
• formula for the rate of reaction

  rate of reaction= amount of reactants used/time
• what is collison theory

  chemical reactions can only occur when reacting particles collide with eachother, collisons must have sufficent energy
• what is activation energy

  the mininum amount of energy that particles must have to react
• what does the rate of a chemical reaction depend on

  the collision frequency of reacting particles
• whats the effect of concentration on the rate of reaction?

  more concentrated solution=more particles colliding in the same volume of solvent, rate is proportional to the concentration
• effect of temperature on the rate of reaction

  when temperature is increased the particles move faster, they collide more frequently,
• what does a catalyst do to the rate of reaction

  catalysts increase the rate of chemical reactions but are not used up during the reaction
• HOW does the catalyst increase the rate

  catalysts increase the rate of reaction by providing a different pathway for the reaction that has a lower activation energy
• if a reversible reaction is exothermic in one direction


  it is endothermic in the opposite direction, with the same amount of energy transferred
• what is equilibrium


  when the rate of forward reaction and the rate of reverse reaction are equal
• whats le chatelers principle

  if you change the conditions of a reversible reaction the system will try to counteract
• how does temperature effect equililbrium

  if you decrease the temperature the equillibrium will move in the direction of the exothermic direction resulting in more products for the exothermic reaction =

  if you increase the temperature the equilbrium will move in the direction of the endothermic reaction, resulting in more products for the endothermic reaction
• how does pressure effect equilibrium

  if you increase the pressure, the euilibirum tried to reduce it, it moves in the direction where there are fewer molecules of gas. +

  if you decrease the pressure, the equilibrium tries to increase it, it moves in the direction where there are more molecules of gas
• how does concentration effect equilibrium

  if you increase the equilibrium of the reactants the system tries to decrease it by making more products +

  if you decrease the concentration of products the system tries to increase it again by reducing the amount of reactants