hydroxides & sulfates

• What is the solubility trend for group 2 metal hydroxides down the group?

  More soluble down the group
• What is the solubility trend for group 2 metal sulfates down the group?

  Less soluble down the group
• What are the solubility characteristics of group 2 hydroxides and sulfates for magnesium, calcium, strontium, and barium?

  • Magnesium: Hydroxide - Insoluble, Sulfate - Soluble
  • Calcium: Hydroxide - Sparingly soluble, Sulfate - Sparingly soluble
  • Strontium: Hydroxide - Soluble, Sulfate - Insoluble
  • Barium: Hydroxide - Soluble, Sulfate - Insoluble
• How do group 2 metal oxides react with water?

  They form metal hydroxides that dissolve in water
• What is the reaction equation for a group 2 oxide reacting with water?

  MO(s) + H2O(l) ➔ M(OH)2(aq)
• What happens to the pH of solutions as the solubility of group 2 hydroxides increases down the group?

  The pH of the solutions increases
• What is the exception to the solubility trend of group 2 oxides?

  MgO reacts slowly and has low solubility
• What are some applications of group 2 elements and compounds?

  • Magnesium in titanium extraction
  • Calcium hydroxide for neutralising soil acidity
  • Magnesium hydroxide as an antacid
  • Barium sulfate in medical imaging
  • Calcium oxide and calcium carbonate in sulfur dioxide removal
• How does magnesium assist in titanium extraction?

  Acts as a reducing agent in reactions
• What is the reaction for titanium extraction using magnesium?

  TiCl4(l) + 2Mg(s) ➔ Ti(s) + 2MgCl2(s)
• What is the role of calcium hydroxide in agriculture?

  Neutralises soil acidity to raise pH
• What is the ionic equation for the neutralisation of soil acidity by calcium hydroxide?

  H+(aq) + OH−(aq) ➔ H2O(l)
• How does magnesium hydroxide function as an antacid?

  Neutralises stomach acid by reacting with HCl
• What is the ionic equation for the neutralisation by magnesium hydroxide?

  H+(aq) + OH−(aq) ➔ H2O(l)
• What is the purpose of barium sulfate in medical imaging?

  Highlights soft tissues for X-ray imaging
• How is barium sulfate administered for imaging?

  Mixed into a liquid suspension and swallowed
• How does barium sulfate help in diagnosing conditions?

  Absorbs X-rays to make organs visible
• What is the role of calcium oxide and calcium carbonate in sulfur dioxide removal?

  React with SO2 to form calcium sulfite
• What is the reaction for calcium oxide reacting with sulfur dioxide?

  CaO(s) + SO2(g) + H2O(l) ➔ CaSO3(s) + H2O(l)
• What is the reaction for calcium carbonate reacting with sulfur dioxide?

  CaCO3(s) + SO2(g) + H2O(l) ➔ CaSO3(s) + H2O(l) + CO2(g)