acids, bases and salts

• What can indicators distinguish between?

  Acidic, alkaline, and neutral solutions
• What are the colors of litmus for different solutions?

  • Acid: Red
  • Neutral: Purple
  • Alkali: Blue
• What are the colors of methyl orange for different solutions?

  • Acid: Red
  • Neutral: Orange
  • Alkali: Yellow
• What are the colors of phenolphthalein for different solutions?

  • Acid: Colourless
  • Neutral: Colourless
  • Alkali: Pink
• What does the Universal Indicator indicate?

  It shows acidity and alkalinity via colors
• What is the pH scale range?

  1 to 14
• What is an acid?

  A substance forming H+ ions in water
• What is hydrochloric acid's formula?

  HCl
• What is sulphuric acid's formula?


  H2SO4
• What is nitric acid's formula?

  HNO3
• What is a base?

  A substance that neutralizes an acid
• What are examples of bases?

  Copper oxide, sodium hydroxide, calcium carbonate
• What is an alkali?

  A soluble base forming OH- ions in water
• What is the formula for sodium hydroxide?

  NaOH
• What is the formula for ammonia?

  NH3
• What is the formula for ammonium hydroxide?

  NH4OH
• What is the reaction between an acid and a base called?

  Neutralisation
• What is the neutralisation equation?

  H+ + OH- → H2O
• What is an acid in terms of protons?

  It is a proton donor
• What is a base in terms of protons?

  It is a proton acceptor
• What are the three reactions of acids?

  1. Metal + Acid → Metal Salt + Hydrogen
  2. Carbonate + Acid → Metal Salt + Water + Carbon Dioxide
  3. Base + Acid → Metal Salt + Water
• What is the reaction of zinc with hydrochloric acid?

  Zinc chloride + Hydrogen
• What is the reaction of copper carbonate with sulphuric acid?

  Copper sulphate + Water + Carbon Dioxide
• What is the reaction of calcium oxide with nitric acid?

  Calcium nitrate + Water
• What is the reaction of sodium hydroxide with hydrochloric acid?

  Sodium chloride + Water
• How can soluble salts be obtained from solution?

  • Evaporate off half the water
  • Leave to evaporate slowly
  • This process is called crystallisation
• How are insoluble salts made?

  • By precipitation reactions
  • Two soluble salts are mixed
  • The insoluble salt is filtered, washed, and dried
• What is an example of making silver chloride?

  Silver nitrate + Sodium chloride
• What is an example of making copper carbonate?

  Copper sulphate + Potassium carbonate
• What is an example of making calcium sulphate?

  Calcium chloride + Ammonium sulphate
• What are the rules for the solubility of salts?

  • All sodium, potassium, and ammonium salts; all nitrates are soluble
  • all chlorides except AgCl and PbCl are soluble
  • all sulphates except BaSO4, CaSO4, PbSO4 are soluble
  • Most carbonates except Na2CO3, K2CO3, NH4CO3 are insoluble
  • most metal hydroxides except NaOH, KOH, NH4OH is insoluble
  • Ca(OH)2 is slightly soluble
• What is a titration?

  An experiment to find precise solution volumes
• What is the procedure for a titration?

  1. Draw 25cm3 of alkali into a pipette
  2. Add indicator to alkali
  3. Add acid from burette while swirling
  4. Note burette reading when indicator changes color
  5. Repeat titration for accuracy