2.16 - 2.18 chem

• 0-3 pH


  strongly acidic
• 4-6


  weakly acidic
• 7


  neutral
• 8-10


  weakly alkaline
• 11-14


  strongly alkaline
• Acid - Alkali indicators

  substances (usually organic compounds) that change color as a function of pH
• litmus


  Acid - Red

  Alkali - Blue
• Methyl orange


  acid - red

  alkali - yellow
• phenophthalein


  acid - colorless

  alkaline - pink
• universal indicator


  acid - red

  alkaline - blue
• What color is litmus in a neutral solution

  purple
• what ions do acids produce when dissolved in water

  H+
• HCl and sodium hydroxide equation

  HCl (l) + NaOH (aq) --> NaCl(aq) + H2O (l)
• how do we write HCl (aq) ?

  H+ (aq) + Cl- (aq)
• what are bases


  substances that neutralize acids by combining with the hydrogen ions
• what are alkalis


  substances that lead to an increase in OH- ions when dissolved in water
• what do we do to find the pH if the pOH is given?

  subtract by 14
• what are metal oxides

  bases
• acid react with bases and alkalis to form a .... reaction


  neutralization
• what is a titration

  when a solution of known concentration is used to determine the concentration of an unknown solution
• what is an indicator used in the titration ?

  to observe the endpoint of the titration
• Hydrochloric acid


  HCl
• nitric acid


  HNO3
• sulfuric acid


  H2SO4
• ethanoic acid


  CH3COOH
• Phosphoric Acid


  H3PO4
• metal + dilute acid

  metal + dilute acid -> salt + hydrogen gas
• metal oxide + dilute acid

  metal oxide + dilute acid --> salt + water
• metal hydroxide + dilute acid

  metal hydroxide + dilute acid --> salt + water
• metal carbonate + dilute acid

  metal carbonate + dilute acid --> salt + carbon + water
• are metal oxides soluble ?

  few are
• K2 + H2O ->

  KOH
• which oxide SLIGHTLY dissolves?

  calcium oxide
• Are metal hydroxides soluble?

  few are
• Which hydroxides are soluble?

  sodium, potassium, ammonium
• Hydrogen gas test


  squeaky pop
• Oxygen gas test


  Relights a glowing splint
• Carbon dioxide test


  Turns limewater milky
• Chlorine gas test


  Bleaches damp litmus paper (red - blue - white)
• Ammonia test


  Turns damp red litmus paper blue