Chem E lec 8 Acid and Base

• Acid dissociates in water to form H + Ions (Hydrogen ions)
• What are strong acids

  1. Hydrochloric acid (HCl)
  2. Sulfuric acid (H2SO4)
  3. Nitric acid (HNO3)
• What are weak acids

  1. Ethanoic acid (CH3COOH)
  2. Carbonic acid (H2CO3)
• Why are they called strong acids?

  This is because strong acids ionises completely/fully in water.
• Why are they call weak acids?

  Because weak acids ionises partially in water
• Name me the three acids reactions?

  1. Acid + Base -> Salt + Water
  2. Acid + reactive metal -> Salt + hydrogen
  3. Acid + carbonate -> Salt + water + carbon dioxide
• Name me the three unreactive metals?

  1. Copper
  2. Sliver
  3. Gold
• List the most reactive metal to the least reactive ?

  Potassium

  Sodium

  Calcium

  Magnesium

  Aluminium

  Zinc

  Iead PB

  Lithium

  Hydrogen

  Copper

  Sliver

  Gold
• Why is sodium stored under oil?

  Since sodium is a very reactive metal, it minimise the reaction between oxygen and water vapour in the air.
• alkali dissociates in water to produce OH- ions (hydroxide ions)
• acid/alkali only show their properties when they are dissolved in water because acid/alkalki ionises in water to produce ions which then carry out the properties
• how to test for the gas that is produced when acid reacts with metal?

  By carrying out lighted splint test, place it near the mouth of the test tube and if hydrogen is present, the lighted splint will extinguish with a 'POP' sound.
• How to test for the gas that is produced when acid reacts with carbonate?

  By carrying out limewater test, bubble the gas through limewater and if carbon dioixde is present, white precipitate is formed.
• whats a base?

  base is a substance that reacts with acid to form salt.
• a base contains either oxide or hydroxide ions
• most bases are either metal oxide or metal hydroxide
• what is an alkali?

  alkali is a base which is soluble in water, it is a substance that dissolve in water to produce OH- ions.
• most bases are insoluble except?

  except :

  all group 1 metal oxide or hydrpxode

  certaom grp II metaln hydroxide

  and aqueous ammonia
• what are some examples of strong and weak bases?

  strong base : sodium hydroxide, calcium hydroxide, potassium hydroxide

  weak base : aqueous ammonia
• what happens when ammounium dissolve in water?

  it becomes ammonia
• NH3 + H20 -> NH4+ + OH-
• Alkali turns litmus paper from red to?

  blue
• reaction of bases?

  acid + base -> salt + water

  acid + ammonium salt -> salt + water + ammonia gas
• what is the test for the gas produce when base reacts with ammonium salt?

  by carrying out litmus paper test, use moist litmus red paper, pungent gas turns moist red litmus paper blue.
• what are the 4 oxides?

  basic, amphoteric, neutral and acidic oxides
• for basic oxides and amphoteric, it is both metal + oxygen, thus making them ionic compounds and exists as solid at r.t.p
• for neutral and acidic oxides, they are both non-metal + oxygen, thus making them covalent compounds, hence, they exists as gas at r.t.p
• basic oxides consist of?

  any metal oxides, like sodium, copper (II), calcium oxides
• What do basic oxides reacts with?

  it reacts with acid to form salt and water.
• What do amphoteric oxides consist of?

  it consist of ZAP. Zinc oxide, Aluminium oxide and Lead oxide.
• what do amphoteric oxides reacts with?

  it reacts with both acid and base to form salt and water.
• what do neutral oxide consist of?

  monoxides and water. exmaple, nitrogen and carbon monoxide.
• what do neutral oxide reacts with?

  it reacts with nothing.
• what do acidic oxides consist of?

  acidic oxides consist of non-metal oxides like, carbon dioxide, ntirogen dioxide, sulfur dioxide.
• what do acidic oxides reacts with?

  acidic oxides reacts with base to form salt and water
• For acids, universal indicator turns from?

  green to red
• for alkali, universal indicator turns from green to ?

  blue
• strong acids in colour are usually?

  red
• weak acids are usually in what colour?

  orange/yellow
• neutral is what colour?

  green