reactivity of metals

• Alkali Metals in Water


  Reacts to produce alkaline solutions and release hydrogen gas. Examples: 2Na + H2O → 2NaOH + H2
• Alkali Metals and Oxygen


  Reacts to produce oxides and release heat. Examples: 4K + O2 → 2K2O
• Alkali Metals and Acids


  Reacts to produce salts and release hydrogen gas. Examples: Na + HCl → NaCl + H2
• Alkali Metals


  Elements in Group 1 (formerly Group Ia) of the periodic table. Examples: Potassium, Sodium, Lithium, Rubidium, Caesium, Francium
• Products of Alkali Metals and Water


  Alkaline solution (e.g. NaOH, KOH) and Hydrogen gas (H2)
• Products of Alkali Metals and Oxygen


  Oxide (e.g. K2O) and Heat
• Products of Alkali Metals and Acids


  Salt (e.g. NaCl) and Hydrogen gas (H2)
• Why Alkali Metals React with Water


  High reactivity of outermost electron, allowing it to readily donate to water molecules, forming a covalent bond
• Electron Transfer


  Electron from alkali metal donates to water molecule, forming an alkaline solution and releasing hydrogen gas
• Formation of Alkaline Solution


  Alkali metal ion (M+) and hydroxide ion (OH-) are formed, resulting in an alkaline solution (pH>7)
• Hydrogen Gas Release


  Electrons from water molecule combine with alkali metal ions, releasing hydrogen gas (H2)
• pH of Alkali Metal Solution


  The pH of the solution is greater than 7, making it basic or alkaline
• Why is the pH High?


  Due to the formation of hydroxide ion (OH-) and the removal of hydrogen ions (H+) from the solution