3rd QT Long Test

• All forms of matter are made up of particles
• Atoms are described as the building blocks of matter
• Different kinds of atoms combine in various ways, leading to the existence of many different things around us
• Basic principles of the particulate model of matter:

  • All matter is made of tiny particles
  • There is empty space in between the particles
  • The particles are in constant motion
  • There are forces that act between the particles
• Solid:

  • Definite shape
  • Particles are close to each other in an orderly arrangement
  • Definite volume
  • Strong attraction between the particles
  • Low compressibility
  • High density
  • Particles completely occupy a given space
  • Does not flow easily
  • Particles are found in fixed positions
• Liquid:

  • No definite shape
  • Particles are not neatly arranged
  • Definite volume
  • Strong attraction between the particles
  • Low compressibility
  • Lower density than solids
  • Absence of neat arrangement between particles
  • Flows easily
  • Particles slide past one another
• Gas:

  • No definite shape
  • Particles are in constant motion and far apart
  • No definite volume
  • Large spaces in between the particles
  • High compressibility
  • Low density
  • Weak interactions between particles
  • Flows easily
  • Particles can easily slide past one another
• Phase Changes:

  • Changes in the physical state of any matter
  • Occur by absorption or release of energy usually in the form of heat
  • Involve the rearrangement of the particles in a given material
• Subatomic Particles:

  • Electrons:
  • Negatively charged particles found in all atoms
  • Discovered from the cathode ray experiments in 1897 by Sir Joseph John Thomson
  • Protons:
  • Positively charged particles found in the nucleus
  • Same magnitude as that of the electron but opposite in sign
  • Discovered by Eugene Goldstein
  • Neutrons:
  • Particles with a neutral charge found in the nucleus
  • Discovered by Sir James Chadwick
• • The number of protons defines the element, and the number of neutrons defines the isotopes of an element
• Identity of an Atom:

  • Atoms of the same element are alike and different from atoms of other elements according to Dalton's atomic theory
  • Atomic number (z) is unique to a given element and indicates that no two elements have the same atomic number and the same number of protons
  • Isotopes are atoms of an element that have the same atomic number but differ in mass
  • Nuclide is an atom of a specific isotope identified using their mass number (A) which is the sum of the number of protons and neutrons
• Ion:

  • Charged particle of the same element formed when electrons are removed or added to a neutral atom
  • Cation is a positively charged ion formed when an electron is removed
  • Anion is a negatively charged ion formed when an electron is added
• APE MAN:

  • Atomic Number = Proton = Electron
  • Mass Number - Atomic Number = Neutron
• Basic principles of the particulate model of matter:

  • All matter is made of tiny particles
  • There is empty space between the particles
  • The particles are in constant motion
  • There are forces that act between the particles
• Different kinds of atoms combine in various ways, leading to the diversity of substances around us
• Solid:

  • Definite shape
  • Particles are close together in an orderly arrangement
  • Definite volume
  • Strong attraction between particles
  • Low compressibility
  • High density
  • Does not flow easily
  • Particles are found in fixed positions
• Liquid:

  • No definite shape
  • Particles are not neatly arranged
  • Definite volume
  • Strong attraction between particles
  • Low compressibility
  • Lower density than solids
  • Flows easily
  • Particles slide past one another
• Gas:

  • No definite shape
  • Particles are in constant motion and far apart
  • No definite volume
  • Large spaces between particles
  • High compressibility
  • Low density
  • Weak interactions between particles
  • Flows easily
  • Particles can easily slide past one another
• Phase Changes:

  • Changes in physical state of matter
  • Occur by absorption or release of energy, usually in the form of heat
  • Involves the rearrangement of particles in a given material
  • Melting: Solid to liquid, heat entering the system
  • Freezing: Liquid to solid, heat leaving the system
  • Evaporation: Liquid to gas, heat entering the system
  • Condensation: Gas to liquid, heat leaving the system
  • Sublimation: Solid to gas, heat entering the system
  • Deposition: Gas to solid, heat leaving the system
• Subatomic Particles:

  • Electrons: Negatively charged particles found in all atoms, discovered from the cathode ray experiments in 1897 by Sir Joseph John Thomson
  • Protons: Positively charged particles found in the nucleus, same magnitude as electrons but opposite in sign, discovered by Eugene Goldstein
  • Neutrons: Particles with neutral charge found in the nucleus, discovered by Sir James Chadwick
• Identity of an Atom:

  • Atoms of the same element are alike and different from atoms of other elements
  • Atomic number (Z) is unique to a given element, indicating no two elements have the same atomic number and same number of protons
  • Isotopes: Atoms of an element with the same atomic number but different mass
  • Nuclide: Atom of a specific isotope identified using their mass number (A), which is the sum of protons and neutrons
  • Ion: Charged particle of the same element formed when electrons are removed or added to a neutral atom
• • Cation: Positively charged ion formed when an electron is removed
  • Anion: Negatively charged ion formed when an electron is added
• APE MAN:

  • Atomic Number = Proton = Electron
  • Mass Number - Atomic Number = Neutron