PHYSICAL SCIENCE

• Atom


  Smallest unit that makes up all matter
• Subatomic particles


  • Proton
  • Neutron
  • Electron
• Element


  A pure substance that represents the species (variety) of a specific atom
• Isotopes


  Atoms of the same element but with different atomic mass (different number of neutrons)
• Element


  Identity of an atom
• Atom


  Shows the variety of an element
• Proton


  Positively charged particle located in the nucleus along with the neutron
• Neutron


  Uncharged particle
• Electron


  Negatively charged particle located around the nucleus
• There are many theories to explain the origin of the Universe, but the most sound is the BIG BANG
• Big Bang Theory


  Postulates that the universe emerged from a state of enormous density and energy. Everything came from a single point and expanded to now what we call the universe.
• Georges Lemaitre


  Proposed the Big Bang theory
• Georges Henri Joseph Édouard Lemaître: 'A French priest and was coined for the idea of the expanding universe.'
• Evidences of the Big Bang

  • Cosmic expansion, discovered by Edwin Hubble
  • Cosmic Microwave Background, discovered by George Gamow
  • Primordial or Big Bang Nucleosynthesis
• Nucleosynthesis


  The formation of atomic nuclei (center of atoms protons and neutrons)
• Nucleosynthesis occurred right after the Big Bang
• Nucleosynthesis


  Started as quarks forming the protons and neutrons
• Types of Nucleosynthesis


  • Big Bang Nucleosynthesis
  • Stellar Nucleosynthesis
  • Supernova Nucleosynthesis
• Stars


  Must have energy to exist for a certain length of time
• Energy source of stars

  1. Nuclear fusion reactions between light elements

  2. Release of a huge amount of energy

  3. Keeps the star hot
• Atoms collide and alters atomic structures and releases an enormous quantity of energy
• The energy release is manifested as the light emitted by the stars
• Nuclear fusion in the core of a star

  Hydrogen is converted to helium
• As stars age they run out of fuel
• Massive stars undergo supernova (explosion of a star)
• The explosion results in the formation of elements heavier than iron, Fe
• Big Bang Nucleosynthesis


  Formation of light elements, Hydrogen and Helium by combination of protons and neutrons right after the Big Bang
• Lithium was also formed through Big Bang Nucleosynthesis
• Stellar Nucleosynthesis


  • Formation of elements in the stars' interior
  • Occurs through nuclear fusion and electron capture
  • Responsible for the formation of elements heavier than Helium, He until Iron, Fe
• Two types of Neutron Capture

  • s-process (slow)
  • r-process (rapid)
• 1. process (slow)


  Addition of neutron is so slow that beta decay happened before another neutron is added to the nucleus
• 1. r-process

  Fast capture of neutron before radioactive decay occurs
• Astrochemist


  Part Astronomer and part Chemist who intensely studies the periodic table within the context of space rather than of Earth
• Astrochemists


  • Observe stars
  • Examine, analyze, and dissect stars
  • Study the different aspects of all the fascinating objects in the universe on a molecular level
  • Aim to answer questions how they were formed
• 1. s-process

  Happens when there is slow rate of capturing neutron while there is a faster rate of radioactive decay
• Stellar nucleosynthesis


  Process by which elements are created within stars
• Tri-Alpha process


  Conversion of helium nuclei to carbon
• Supernova nucleosynthesis


  Process by which heavier elements after iron are formed
• Proton-proton chain


  Nuclear fusion reaction where hydrogen is converted to helium
• Physical Science