Group 2: the alkaline earth metals

• What are group 2 elements calls

  Alkaline earth metals
• What is the trend in reactivity for group 2

  increases down the group
• Trend in atomic radiua


  Atoms get larger as there is more protons. There’s a weaker attraction between outer shell and nucleus due to more shielding
• What are the properties

  They are:

  shiny

  Conduct when solid

  Malleable

  ductile

  Sonorous

  Reactive with oxygen water and acids

  Form white ionic compounds
• How does magnesium react with cold water?

  Very slowly
• How does magazine magnesium react with steam?

  When magnesium is heated, it reacts with steam to produce magnesium oxide and hydrogen
• What’s the equitation of mg with steam

  The reaction of magnesium with steam is:

  Mg (s) + H2O(g) —> MgO (s) + H2 (g)
• What are the three observations when magnesium reacts with steam

  The gas that is produced burns because Hydrogen is flammable

  
  

  magnesium glows brightly without heat because it’s an exothermic reaction

  
  

  A white solid is formed as magnesium oxide is produced
• What is the equation for hydrogen burning?

  H2 + 1/2 O2 —> H2O
• What is the reaction of calcium with cold water?

  Calcium reacts with water to produce calcium hydroxide and hydrogen
• What is the chemical equation for the reaction of calcium with cold water?

  Ca (s) + 2H2O (l) → Ca(OH)2 (aq) + H2 (g)
• What products are formed when calcium reacts with cold water?

  Calcium hydroxide and hydrogen gas
• How soluble is calcium hydroxide in water?

  It is only slightly soluble in water
• How does the reactivity of calcium with water compare to magnesium?

  Calcium reacts faster than magnesium with water
• How does the reactivity of calcium with water compare to Group 1 metals like sodium?

  Calcium reacts slower than Group 1 metals
• What are the three observations of reaction of calcium with cold water?

  Bubbles form and a squeaky pop is made when a little splint is in the presence of the reaction because hydrogen is made

  
  

  it becomes hot as the reaction is exothermic

  
  

  It becomes cloudy as calcium oxide is only sparingly soluble
• What is the pH of the solution?

  It is 12 as alkali is produced
• What is the equation for Strontium with water?

  Sr (s) + 2H2O (l) → Sr(OH)2 (aq) + H2 (g)
• What is the equation for Barium with water?

  Ba (s) + 2H2O (l) → Ba(OH)2 (aq) + H2 (g)
• What happens to the electronic structure during oxidation of metals?

  The metal atoms lose two electrons
• What ions are formed during the oxidation of Strontium and Barium?

  Sr²+ or Ba²+ ions
• Why do metals become more reactive down the group?

  Outer electrons are further from the nucleus
• What effect does electron shielding have on metal reactivity?

  It reduces nuclear attraction
• How does the distance of outer electrons affect their loss?

  Electrons are lost more easily
• Why shouldn't water be used on magnesium fires?

  Magnesium reacts with water to produce hydrogen gas
• What can hydrogen gas form when mixed with air?

  An explosive mixture
• Why is water not a safe extinguisher for magnesium fires?

  It can lead to an explosive reaction
• What is the equation for the formation of TiCl4?

  TiO₂ + 2C + 2Cl₂ → TiCl4 + 2CO
• What is the equation for the reduction of TiCl4 with Mg?

  TiCl4 + 2Mg → Ti + 2MgCl2
• What is the half-equation for magnesium oxidation?

  Mg → Mg2+ + 2e-
• How does magnesium act as a reducing agent?

  It loses electrons and reduces titanium ions.
• Why is magnesium more reactive than titanium?

  Magnesium can reduce titanium from TiCl4.
• What is the use of calcium hydroxide in agriculture?

  To neutralize acidic soil for crop growth.
• What is the equation for calcium hydroxide reacting with hydrochloric acid?

  Ca(OH)2 + 2HCl → CaCl2 + 2H2O
• How does magnesium hydroxide function in medicine?

  It neutralizes stomach acid to relieve indigestion And heartburn
• What is the equation for magnesium hydroxide reacting with hydrochloric acid?

  Mg(OH)2 + 2HCl → MgCl2 + 2H2O
• What environmental issue is caused by sulfur dioxide (SO₂)?

  It contributes to acid rain damaging ecosystems.
• What does sulfur dioxide react with to form sulfuric acid?

  It reacts with water and oxygen in the atmosphere.
• What is the reaction of calcium oxide with sulfur dioxide?

  CaO + SO2 → CaSO3 calciumsulfite
• What does calcium carbonate produce when it reacts with sulfur dioxide?

  It produces calcium sulfite and carbon dioxide.

  CaCO3 + SO2 —> calcium sulfite (CaSO3) + cO2