paper 2

• What is the term for how quickly a reaction happens?

  The rate of reaction
• How is the rate of reaction defined?

  It is the change in a quantity divided by time.
• What can the quantity in the rate of reaction refer to?

  It can refer to the mass or volume of gas produced.
• What does measuring the rate of reaction typically give you?

  It gives you the mean rate of reaction.
• What happens to the solution in the hydrochloric acid and sodium thiosulfate experiment?

  The solution turns cloudy, indicating increased turbidity.
• How can you determine when to stop the timer in the turbidity experiment?

  When the cross on the paper is no longer visible from above the flask.
• What effect does increasing temperature have on the rate of reaction?

  It decreases the time it takes for the reaction to occur.
• How can the volume of gas produced in a reaction be measured?

  By using a gas syringe connected to the reaction vessel.
• What does a graph of gas volume against time typically look like?

  It starts steeply and then levels out or plateaus.
• How can you find the rate of reaction at any time from a graph?

  By drawing a tangent at that point and calculating the change in quantity divided by time.
• What factors can increase the rate of a reaction?

  Increasing concentration, pressure, and surface area of reactants.
• Why does increasing temperature increase the rate of reaction?

  Particles move more quickly and collide with more energy.
• What is the role of a catalyst in a reaction?

  A catalyst reduces the activation energy needed for a reaction.
• What happens in a reversible reaction?

  The products can return to their original reactants.
• What is the prime example of a reversible reaction mentioned?

  The Haber process.
• What occurs in a closed system at equilibrium?

  The rates of the forward and reverse reactions are equal.
• What does Le Chatelier's principle state?

  If a system at equilibrium is subjected to a change, it will adjust to counteract that change.
• What happens if the pressure of a gas reaction is increased?

  The reaction will favor the side with fewer moles of gas.
• What effect does increasing temperature have on an exothermic reaction?

  It favors the endothermic reaction.
• What is the general formula for alkanes?

  C$_n$H$_{2n+2}$
• What do all alkane names end with?

  They end with "ane".
• What is the process used to separate different length alkanes from crude oil?

  Fractional distillation.
• Why do longer alkanes have higher boiling points?

  They have stronger intermolecular forces that require more energy to overcome.
• What is LPG?

  Liquid petroleum gas, consisting of short-chain alkanes.
• What is the main use of petrol?

  It is used as fuel in cars.
• What is produced during complete combustion of alkanes?

  Carbon dioxide and water.
• What is the difference in viscosity between longer and shorter alkanes?

  Longer alkanes are more viscous, while shorter alkanes are less viscous.
• What is the functional group of alcohols?

  It is the hydroxyl group (-OH).
• What do the names of alcohols end with?

  They end with "ol".
• What happens when alcohols undergo complete combustion?

  They produce carbon dioxide and water.
• What is produced when an alcohol is oxidized without combustion?

  A carboxylic acid is produced.
• What is the functional group of carboxylic acids?

  It is the carboxyl group (-COOH).
• What is the process of polymerization?

  It is the joining of monomers to form a polymer.
• What is the repeating unit in addition polymerization?

  It is the monomer with a double bond.
• What is condensation polymerization?

  It is the joining of two monomers with the release of water.
• What are amino acids?

  They are the building blocks of proteins.
• What is DNA?

  It is a large molecule that stores genetic code.
• What is the purpose of chromatography?

  To separate substances in a mixture.
• How can the purity of a substance be tested?

  By testing its melting point or boiling point.
• What are the key factors affecting the rate of reaction?

  • Concentration of reactants
  • Pressure of gas reactants
  • Surface area of solid reactants
  • Temperature
  • Presence of a catalyst