abiotics biotics

• What are abiotic factors in an ecosystem?


  Abiotic factors are the non-living components of an ecosystem.
• How does sunlight function as an abiotic factor?


  Sunlight is the amount and intensity of light available in an ecosystem.
• What is the significance of water as an abiotic factor?


  Water refers to the availability and quality of water in an ecosystem.
• What is the role of temperature as an abiotic factor?


  Temperature is the degree of heat or cold in the environment.
• What is the total mass of one water molecule according to Dalton's theory?

  18 mass units
• What does Dalton's atomic theory state about atoms in terms of creation and destruction?

  Atoms cannot be created, destroyed, or changed
• What is the main component of Rutherford's experiment depicted in the images?

  • A lead block containing radium as the radioactive source
  • A thin gold foil
  • A circular detector
• How did Rutherford's experiment disprove the plum pudding model of the atom?

  • The plum pudding model predicted α-particles would pass through undeflected or with slight deflections
  • The experiment observed strong deflections of α-particles, indicating a concentrated positive charge in the nucleus
• What conclusion did Rutherford draw from the deflection of some alpha particles?

  Atoms have a dense nucleus at the center
• What was the significance of Dalton's atomic theory?


  It provided the basic foundation for modern atomic theory
• What is the mass of one hydrogen atom according to Dalton's theory?

  1 mass unit
• What are the key postulates of Dalton's Atomic Theory?

  • All matter is made of atoms
  • Atoms are indivisible and indestructible
  • All atoms of an element are identical in mass and properties
  • Atoms of different elements have different masses and properties
  • Atoms combine to form compounds
• How did Dalton's theory explain the formation of water from oxygen and hydrogen atoms?

  • One oxygen atom combines with two hydrogen atoms
  • The combined mass of the atoms forms a water molecule with a mass of 18 mass units
  • The atoms are joined, not broken down
• What are electrons said to orbit in according to Bohr's model?

  Specific electron shells
• What is the key difference between electrons and the positively charged matter in an atom?

  • Electrons are negatively charged particles orbiting the nucleus
  • Positively charged matter consists of protons and neutrons, located in the nucleus
• What does Thomson's Plum Pudding Model depict the atom as?

  A positively charged sphere
• What are the key components of Thomson's Plum Pudding Model?

  • Positively charged sphere
  • Electrons embedded like plums
  • Uniform distribution of electrons
• What is the orientation quantum number and its possible values for p, d, and f orbitals?

  • p orbital: $m_l$ = -1, 0, 1
  • d orbital: $m_l$ = -2, -1, 0, 1, 2
  • f orbital: $m_l$ = -3, -2, -1, 0, 1, 2, 3
• What is the principal quantum number (n) for an f orbital?

  ≥4
• What type of charge do electrons carry?

  Negative charge
• What was the purpose of the lead block and detector in Rutherford's experiment?

  • Lead block shielded the experiment from external radiation
  • Detector measured the number and direction of scattered particles
• What does Dalton's atomic theory propose about matter?

  All matter is made of tiny indivisible atoms
• How do atoms combine during chemical reactions?

  In simple whole-number ratios
• How does Bohr's model help explain atomic behavior?


  It shows why atoms behave the way they do
• What is the structure of Thomson's atomic model?

  Positive sphere
• What did the strongly deflected α-particles in Rutherford's experiment indicate about the structure of the atom?

  • Most of the atom's mass is concentrated in a small, dense region called the nucleus
  • The nucleus carries a positive charge
  • The atom is mostly empty space
• Approximately what fraction of α-particles were strongly deflected in Rutherford's experiment?

  About 1 in 10,000
• Why was gold chosen as the foil material in Rutherford's experiment?

  Because it is a heavy metal and can be made into a thin foil
• What does it mean for electron energy to be quantized?

  It exists only at specific values
• What does the probability distribution in the quantum mechanical model indicate?

  Where electrons are most likely to be found
• What are the main differences between the atomic models discussed?

  • Dalton's: No nucleus, no electrons
  • Thomson's: Positive sphere, embedded electrons
  • Rutherford's: Dense nucleus, orbiting electrons
  • Bohr's: Nucleus, quantized electron shells
  • Quantum Mechanical: Nucleus, orbitals with probability distributions
• What are the specific positions where electrons can be found called?

  Energy levels
• In what year did Rutherford conduct his experiment with alpha particles?

  1911
• What charge does the nucleus of an atom carry according to Rutherford's model?

  Positive charge
• What type of particles were used in Rutherford's gold foil experiment?

  α-particles
• What model of the atom was proposed by Rutherford based on his gold foil experiment?

  The nuclear model
• What were the main conclusions drawn from Rutherford's gold foil experiment?

  • The atom has a small, dense, positively charged nucleus
  • The nucleus contains most of the atom's mass
  • Most of the atom is empty space
• What surprising result did Rutherford find when firing alpha particles at gold foil?

  Most particles passed straight through
• What are the primary subatomic particles of an atom?

  Protons, neutrons, and electrons
• What are orbitals in the quantum mechanical model?

  Regions of space where electrons are likely found