1. Experimental chemistry

• Conversion of tonne to kilogram?

  1t = 1000kg
• What is the SI unit of temperature?

  Kelvin (k)
• Conversion of degree celsius to kelvin?

  1 Kelvin = degree celsius + 273
• SI unit for volume?

  Cubic metre (m^3)
• Conversion from m^3 to dm^3 to cm^3?

  1m^3 = 1000dm^3

  1dm^3 = 1000cm^3
• How to measure mass? What is the accuracy of such apparatus?


  1. Beam balance (+-0.1g)
  2. Electronic balance (+-0.01g)
• How to measure temperature? What is the accuracy of such apparatus?


  1. Digital thermometer (+-0.1 degree celsius)
  2. Temperature sensor and data logger
  3. Mercury/alcohol thermometer (+-0.5 degree celsius)
• How to measure time? What is the accuracy of such apparatus?

  1. Analogue stopwatch
  2. Digital stopwatch
• What apparatus's are used to measure an estimate volume?


  1. Beaker/conical flask
  2. Measuring cylinder
• What apparatus is used to measure an accurate volume? What is the accuracy of such an apparatus?


  1. Burette (+-0.05)
  2. Pipette (fully accurate)
• How to measure volume of gas?

  • Gas syringe
• What are the 4 ways to collect gases?


  1. Displacement of water
  2. Downward delivery
  3. Upwards delivery
  4. Using a gas syringe
• For what gases do I use displacement of water?

  Gases which are insoluble in water
• What are example of gases that are insoluble in water?


  • Hydrogen
  • Oxygen
  • Carbon dioxide
• For what gases do I use downward delivery?


  Gases which are denser than air and soluble in water
• What gases are denser than air and soluble in water?

  • Chlorine
  • Hydrogen Chloride
• For what gases do I use upward delivery?


  For gases which are less dense than air and soluble in water
• What gases are less dense than air and is soluble in water?

  • Ammonia
• When do I use a gas syringe?


  To measure the rate of evolution at which a gas is produced
• What is the solubility and density chart for gases? [MEMORISE]

  
• What are the 3 ways to dry a gas?


  1. Usage of concentrated sulfuric acid
  2. Usage of quickline (solid calcium oxide)
  3. Using fused calcium chloride
• For what gases do I use concentrated sulfuric acid?

  • Acidic gases
  • Do not react with acids
• For what gases do I use quickline?

  For alkaline gases
• What is an example of alkaline gases?

  Ammonia
• When do I use fused calcium chloride?

  • For most gases, except those that reacts with calcium chloride
• Why must calcium chloride be heated before use?

  Since calcium chloride is used to absorb moisture from the air, it must be heated to ensure that it is completely dry
• What are the 4 ways to separate solid-solid mixtures?


  1. Magnetic attraction
  2. Sieving
  3. Use of suitable solvent
  4. Sublimation
• What materials can be used in magnetic attraction?


  Magnetic materials with a non magnetic material
• What materials can be used in sieving?


  Materials with particles of different sizes, with one material having a particle with a pore size smaller than that of the sieve
• What materials can be used in usage of suitable solvent?


  A material which is soluble in the solvent and the other is not
• What materials can be used in sublimation?


  A material that sublimes with one that does not
• Example of substances that sublime?


  • Solid carbon dioxide (dry ice)
  • Iodine
  • Ammonium chloride
• What are the 4 ways to separate solid-liquid materials?

  1. Filtration
  2. Evaporation to dryness
  3. Crystallisation
  4. Simple distillation
• What materials can be used in filtration?


  In soluble solids from liquids
• What materials can be used in evaporation to dryness?

  • A soluble solid (solute) from a solution (solvent)
  • The solvent has a lower boiling point than the solute
• What materials CANNOT be used in evaporation to dryness? What is an example of such a material?


  • Substances that decompose on heating
  • Sugar
• What materials can be used in crystallisation?


  • A soluble solid and a solution

  SUITBALE FOR substances that decompose on heating
• For what substances should crystallisation be used instead of evaporation to dryness?


  Substances that decompose upon heating is suitable for crystallisation, and is not for evaporation to dryness
• What is a saturated solution?


  It is a solution in which no more solute can dissolve in the solvent
• Why do crystals form upon cooling?


  the solubility of the solute decreases as the temperature decreases. When the solution cools, the extra solute that cannot remain dissolved is formed as pure crystals