sci qtr 3

• Volcanic Features


  • Volcano
  • Main Vent
  • Magma chamber
  • Magma
  • Crater
  • Lava flow
  • Lava
  • Secondary Vent
  • Secondary Cone
  • Ash Cloud
  • Ash
• Volcano


  • A vent, hill, or mountain that erupts, releasing molten rocks, rock fragments, and gaseous materials onto Earth's surface

  
• Types of Volcanoes According to Shape

  • Cinder cones
  • Composite
  • Shield

  
• Cinder cones

  • Smith Volcano (known as Mount Babuyan), Taal Volcano

  
• Composite


  • Mount Fuji, Mayon Volcano, Mt. Kanlaon
• Shield


  • Kilauea Volcano, Mauna Loa
• Types of Volcanoes According to Eruptive History

  • Active
  • Dormant
  • Extinct

  
• Active

  • Mount Mayon in Albay, Bicol; Mt. Biliran (Anas) in Leyte, Visayas; Mt. Hibok-hibok in Camiguin, Mindanao
• Dormant


  • Mahagnao Volcano in Burauen, Leyte
• Extinct


  • Mount Guinsiliban in Camiguin Island
• There are 24 active volcanoes in the Philippines, and the majority of them are located in Luzon. The other remaining volcanoes remain dormant and inactive.
• Volcanic Activity: Phases of a Volcanic Eruption

  1. Preparation phase

  2. Eruption phase

  3. Ending phase

  
• Types of Volcanic Eruptions

  • Effusive eruptions
  • Explosive eruptions

  
• Hawaiian

  • 1969 eruption of Mauna Ulu in Hawaii
• Strombolian


  • Eruption of Mt. Mayon in November 2009
• Vulcanian


  • Eruption of Mt. Mayon in April 1968
• Plinian


  • Eruption of Mt. Pinatubo on June 1991
• Phreatic


  • Eruption of Mt. Kanlaon in December 2017
• Phreatomagmatic


  • Eruption of Mt. Taal in January 2020
• Materials Extruded during Eruptions

  • Lava
  • Tephra
  • Volcanic gasses

  
• Lava


  Magma (molten rock) that has been expelled onto Earth's surface
• Tephra


  Pyroclastic materials and rock fragments that are being expelled during volcanic eruptions

  
• Volcanic gasses


  Gasses being released during eruptions, including water vapor, carbon dioxide, and hydrogen
• Pyroclastic Material


  • Volcanic bombs
  • Volcanic Ash
  • Lapilli
  • Volcanic blocks

  
• Volcanic bombs


  • A mass of molten rock that is larger than 64 mm (2.5 inches) in diameter, large and dense pyroclastic rocks that cool in the air before they reach the ground

  
• Volcanic Ash


  • A mixture of powder-sized (2 mm or smaller) rocks, minerals, and gas particles

  
• Lapilli


  • Pyroclastic materials that range from 4 to 32 mm (0.16 to 1.26 inches) in diameter
• Volcanic blocks


  • Pyroclastic materials that are already solid when ejected during eruptions, more angular because they are not shaped and cooled in air just like volcanic bombs, larger than 64 mm in diameter

  
• Good Effects of Volcanic Eruptions

  • Provide an alternative source of energy (geothermal energy)
  • Lava and ash deposits provide valuable nutrients to the soil, making it fertile and good for agriculture
  • May cause long-term effects on climate and may cause global cooling

  
• Harmful Effects of Volcanic Eruptions

  • Volcanic ashes and gasses ejected into the air may cause breathing problems when inhaled
  • Cause damage to crops and properties and may endanger the lives of humans and animals near the area
  • If ash and mud mix with water, a fast-moving mudflow (lahar) may destroy properties and also lives
• Bonding


  The formation of a chemical bond between two or more atoms, molecules, or ions to give rise to a chemical compound
• Gilbert Lewis


  American physical chemist who created Lewis electron dot structure

  
• Octet rule


  An atom needs to attain 8 electrons in its outermost energy level to become stable
• Duplet rule


  Some elements can be stable with two electrons in their shell
• Electron affinity


  Energy associated with an atom gaining an electron, higher electron affinity indicates a stronger attraction for an additional electron
• Electronegativity


  Relative tendency of an atom in a molecule to attract the shared electrons towards itself, helps predict the polarity of bonds and molecules
• Valence shell


  Outermost electrons in an atom's orbital, atoms in here are unstable, valence electrons are found here

  
• Ionic bonding (electrovalent bond)


  Type of bond that involves the complete transfer of valence electron(s) from one atom to another, generates two oppositely charged ions
• Ion


  May be an atom or group of atoms that has gained or lost one or more of its valence electrons, cation (carries net positive charge), anion (carries net negative charge)
• Molecule


  Made up of 2 or more atoms with a definite arrangement that are held together by a chemical bond