Big Bang Theory Quiz

Big Bang Theory

• States the universe originated from a massive explosion 15 billion years ago
• The universe has continuously expanded since then

Lightest Elements Formed in Early Universe

• Hydrogen and Helium

Heavier Elements Formation

• Big Bang Nucleosynthesis: A process where the universe cooled and subatomic particles formed heavier elements
• Nucleosynthesis: The process of creating atomic nuclei from pre-existing protons and neutrons

Big Bang Nucleosynthesis Details

• Favors light isotopes like Hydrogen (1.008) and Helium (4.003)
• These isotopes are denser than elements with larger atomic mass.

Subatomic Particles

• Atom: The smallest unit of matter
• Proton: Positively charged subatomic particle
• Neutron: Subatomic particle with no charge
• Electron: Negatively charged subatomic particle

Nuclear Fusion

• The process of light nuclei fusing to form heavier nuclei
• Isotopes formed during Big Bang nucleosynthesis: H-1, H-2, He-3, He-4, Li-7
• Isotope: A form of an element with the same atomic number but a different atomic mass

Origin of Heavier Elements

• Heavier elements formed billions of years after stars formed
• Stellar nucleosynthesis: The process of forming heavier elements via the fusion of lighter nuclei inside stars

Stellar Nucleosynthesis Processes

• Stars burn hydrogen to form helium.
• Various pathways exist for synthesizing heavier elements including:
  • Carbon-Nitrogen-oxygen cycle
  • Proton-proton fusion
  • Triple alpha process

Elements Heavier than Iron

• Cannot be formed through fusion; tremendous energy is needed for the reaction
• Formed during supernova explosions

Supernova Explosions

• Massive explosions of stars
• Produce heavier elements from neutron capture reactions

Summary of Element Formation

• Three processes formed elements
  • Nucleosynthesis
  • Fusion
  • Neutron capture reaction
• Abundant elements formed via fusion in stars
• Elements heavier than iron formed by neutron capture in supernova

Star Formation

• Occurs when a dense region of molecular clouds collapses
• Fragmentation of clouds forms protostars
• Gravitational force causes temperature increase
• Nuclear reactions begin when temperature reaches 10 million Kelvin
• Neutrino positrons released slow the reactions
• Protostar reaches equilibrium forming a main sequence star

Elements Formed in Main Sequence Stars

• Hydrogen fuses with helium through the proton-proton chain, creating primordial elements
• Helium converts into carbon in the core, while hydrogen converts into helium surrounding it, which signifies the formation of red giants.

Elements Formed in Massive Stars

• Massive stars fuse heavier elements consecutively around the core.
• Elements like carbon, neon, magnesium, silicon, and finally iron form through consecutive fusion steps.
• Process of fusing elements leading to red giant formation

Low-Mass Star Evolution

• Helium in the core converts into carbon.
• Reaction rate decreases.
• Gravitational force squeezes the star.
• Outer material gets blown off.
• Inert carbon core remains: white dwarf formation

Stellar Nucleosynthesis

• Heavier elements form via combining protons/neutrons from lighter nucleuses
• Heavy elements produced from exploding or dead stars, and their abundance changes as stars evolve
• Helium and carbon react to produce oxygen and gamma rays.
• Oxygen and helium combine to form neon and gamma rays.

Additional Nuclear Reactions

• Alpha Emission: A particle with two protons and two neutrons is emitted resulting in a new lighter element
• Beta Emission: A neutron becomes a proton and an electron ejected, resulting in a new element with the same mass number
• Gamma Emission: Gamma rays emitted when a nucleus leaves an excited state

Evidence for Stellar Nucleosynthesis

• Interstellar dusts and gasses exist.
• Infrared radiation emitted during star formation.

Atomic Number and Element Synthesis

• Scientists organize elements by properties and atomic number (number of protons)
• Atomic number increases with addition of a proton. This creates a new element.
• Henry Moseley used atomic number to categorize elements.

Test your knowledge on the Big Bang Theory and the formation of elements in the early universe. Dive into topics like nucleosynthesis, subatomic particles, and nuclear fusion to explore the origins of matter. This quiz will challenge your understanding of cosmic events that shaped our universe.