C3 - Chemical changes

• HCl


  Hydrochloric acid
• H2SO4


  Sulfuric acid
• HNO3 


  Nitric acid
• NaOH 


  Sodium Hydroxide
• MG(OH)2 


  Magnesium Hydroxide
• Al(OH)3


  Aluminium Hydroxide
• Phenolphthalein

  Acid = colourless

  Alkali = pink

  Neutral = colourless
• Methyl orange

  Acid = red

  Alkali = yellow

  Neutral = yellow
• Litmus

  neutral = green

  alkali = purple/blue

  acid = red
• As pH decreases...

  the concentration of H+ ions increase by a factor of 10
• Dilute acid


  Few H+ ions
• Concentrated acid


  lots of H+ ions
• Weak acid (ethanoic acid= COOH)


  partially ionised/ H+ ions partially dissociate
• Strong acid (Hydrochloric acid = HCl) 


  
  

  Fully ionised/ H+ ions fully dissociate
• Bases

  neutralise an acid
• Alkali =

  soluble bases
• Hydrochloric acid makes...

  Chloride salts
• Sulfuric acid makes...

  sulfate salts
• Nitric acid makes..

  Nitrate salts
• By-products

  Oxide = water

  Carbonates = carbon dioxide + water

  Acids = Hydrogen
• Test for Carbon dioxide

  • bubble gas through limewater
  • limewater goes cloudy
• Test for Hydrogen

  • Lit splint in test tube
  • Squeaky pop
• Test for Chlorine

  • Turns blue litmus paper red and bleaches it white
• CORE PRACTICLES (COPPER SULFATE CRYSTALS)

  copper sulfate (insoluble salt) = filtration

  1. Add excess copper oxide into sulfuric acid
  2. When mixture is neutral, filter
  3. Crystallise/evaporate (heat on Bunsen burner with evaporating dish)
• PURE DRY PRECIPTATE

  using silver nitrate and sodium chloride

  1. dissolve NaCl and AgNO3
  2. Mix
  3. Filter
  4. Wash with distilled water
  5. Dry
• INVESTIGATING pH

  1. Measure 20cm3 of HCl, add to conical flask
  2. Use pH paper to measure pH of acid
  3. Measure 0.1g of CaOH
  4. Add to HCl and stir
  5. (Spot onto indicator paper )Measure pH
  6. Repeat
  7. Use graph to find out mass needed 
• SOLUBILITY RULES (SALTS)


  SOLUBLE:

  • all nitrates
  • sodium carbonate/hydroxide
  • potassium carbonate/hydroxide
  • ammonium carbonate/hydroxide
• SOLUBILITY RULES (SALTS)

  INSOLUBILITY:

  • silver chloride
  • lead chloride
  • lead sulfate
  • barium sulfate
  • calcium sulfate
• NEUTRALISATION REACTION


  H+ + OH- --> H2O
• K+


  Potassium ion
• Na+


  Sodium ion
• Li+


  Lithium ion
• Mg2+


  Magnesium ion
• Al3+


  Aluminium
• Fe2+, Fe3+


  Iron ion
• Cl-


  Chlorine ion
• Br-


  Bromine ion
• I-


  Iodine ion
• NO3-


  Nitrate ion
• OH-


  Hydroxide ion