Chemistry

Subdecks (1)

Cards (109)

  • Soluble salts
    • Nitrate
    • Chloride (except Ag, Pb)
    • Group 1 carbonates
  • Insoluble salts
    • Sulfate (except Ba, Ca, Pb)
    • Chloride (Ag, Pb)
    • Rest of carbonates
  • Solubility table
    Helps know whether a salt is soluble or not
  • This solubility table is a 'secret' contributed by Ms Aida (BtVSS, MOE Singapore)
  • Cation test with NaOH
    • Cu2+
    • Fe2+
    • Fe3+
    • Ca2+
    • NH4+
    • Zn2+
    • Al3+
    • Pb2+
  • Cation test with NH3
    • Cu2+
    • Fe2+
    • Fe3+
    • Zn2+
    • Al3+
    • Pb2+
  • Cation test table
    Shows colour changes when salts are added to NaOH or NH3
  • Anion tests
    • Chloride (AgNO3 - white ppt)
    • Carbonate (CO2 - turns limewater chalky)
    • Sulfate (Ba(NO3)2 - white ppt)
    • Nitrate (Al, NaOH - turns red litmus blue)
    • Iodide (Pb(NO3)2 - yellow ppt)
  • Gas tests
    • Ammonia (damp litmus paper turns blue)
    • Carbon dioxide (limewater turns chalky)
    • Chlorine (damp blue litmus paper bleaches)
    • Hydrogen (burning splint makes 'pop' sound)
    • Oxygen (glowing splint glows brighter/bursts into flame)
    • Sulfur dioxide (K2Cr2O7 turns green)
  • Mole concept formulas
    • Mass of sample
    • Volume of gas
    • Number of moles
    • Number of particles
  • All acids change blue litmus red
  • Acids react with metals above hydrogen in reactivity series
  • Acids react with bases to form salt and water
  • Uses of ammonia
    • Manufacture of nitric acid
    • Produce fertilisers
  • Hydrogen can be used as a fuel
  • Ethene (alkene) is used to make plastic
  • Potassium dichromate (VI)
    • Acts as an oxidising agent
    • Turns from orange to green when oxidised
  • Potassium iodide
    • Acts as a reducing agent
    • Turns from colourless to brown when reduced
  • Uses of ethanol
    • Solvent for organic compounds
    • To make alcoholic drinks
  • Something with more carbon content is stronger
  • Fermentation
    • Requires 37°C, enzymes, no oxygen
  • Alkene addition of steam to become alcohol
    • Requires phosphoric acid catalyst, 300°C, high temperature/pressure
  • Alkene addition of hydrogen to become alkane
    • Requires nickel catalyst
  • Fractional distillation of petroleum
    Crude oil boiled, lighter fractions separate at lower boiling points, heavier fractions separate at higher boiling points, fractions collected at different boiling points
  • Electrical conductivity
    Requires moving ions
  • Heat conductivity
    Requires free moving electrons
  • Boiling point
    Depends on strength of electrostatic attraction
  • Why ionic compounds have high boiling point
    Consist of ions held by strong electrostatic attraction, large energy needed to break bonds
  • Why covalent compounds have low boiling point
    Consist of molecules with weak intermolecular forces, small energy needed to break bonds
  • Why ionic compounds conduct in molten/aqueous state
    Ions become free to move and convey charge
  • Why ionic compounds cannot conduct in solid state
    Ions are fixed rigidly by strong electrostatic attraction and cannot move
  • Why attaching magnesium to iron pipes increases their working life
    Magnesium is more reactive than iron, so water reacts with magnesium instead, reducing iron rusting (sacrificial protection)
  • Why copper cannot be used instead of magnesium for sacrificial protection
    Copper is less reactive than iron, so iron would rust faster with copper attached
  • Why hydrogen is more reactive than helium
    Hydrogen has 1 valence electron and can gain 1 more to become stable, helium has 2 valence electrons and is very stable
  • Physical properties of metals
    • Good conductors of heat and electricity
    • High boiling and melting points
    • Malleable and ductile
  • Why copper is recycled
    Copper is expensive and not as abundant as some other metals
  • When naming an ester, you need to consider the structure
  • Magnesium
    Above iron in the reactivity series
  • Sacrificial protection
    1. Water reacts with Magnesium instead of iron
    2. Magnesium gets worn out
    3. Iron rusting is much reduced
  • Copper is below iron in the reactivity series