Science

• Matter


  Anything that has mass and volume
• Atom


  The building block of matter
• All substances are composed of invisible particles called atoms
• Atoms are in constant motion
• The combination of atoms leads to millions of materials with different properties
• Nucleus


  Protons with a positive charge, Neutrons with no charge (neutral)
• Phases of matter


  • Solid
  • Liquid
  • Gas
  • Plasma
• Solid


  • Definite shape, definite volume
• Liquid


  • Definite volume, no definite shape
• Gas


  • No definite shape, no definite volume
• Plasma


  • Atoms in an excited state
• Plasma


  • Lightning, auroras, neon lights
• Particle theory


  All particles are moving, forces of attraction hold particles together
• Particles in a solid

  • Can vibrate in place but cannot flow, held in place by strong forces of attraction, cannot be compressed
• Particles in a liquid

  • Can move around each other, held together by weaker forces of attraction, cannot be compressed
• Particles in a gas

  • Can move freely in all directions, few forces of attraction between particles, can be compressed
• Thermal energy


  The total energy of the particles in a material, including both potential and kinetic
• Average kinetic energy


  Temperature is the average kinetic energy of particles in a substance
• Melting


  Melting point is the temperature at which a solid begins to turn into a liquid
• Liquids flow


  Particles in liquids have more kinetic energy allowing them to overcome their attraction and slide past each other
• Gases


  Particles have enough kinetic energy to overcome the attractions among them so they have no fixed volume or shape
• Evaporation


  Vaporization that occurs at the surface of a liquid, can occur below the liquid's boiling point
• Boiling


  The boiling point is the temperature at which the pressure of the vapour in the liquid is equal to the external pressure
• Diffusion


  The spreading of particles throughout a given volume until they are evenly distributed
• Thermal expansion


  An increase in the size of a substance when the temperature is increased
• Density


  The amount of matter present in an object (mass) compared to the amount of space it occupies (volume)
• Substances less dense than water float, substances more dense than water sink
• Water cycle


  Water evaporates into the air

  Water vapour condenses into clouds

  Water falls as precipitation

  Water returns to the sea
• Metals


  • Lustrous, high melting point, dense, ductile, malleable, good conductors of electricity and heat, react with water and oxygen
• Non-metals


  • Many are gases at room temperature, dull, brittle, not ductile or malleable, low density, low melting point, poor conductors of heat and electricity
• Metalloids


  • Have properties of both metals and non-metals, can be shiny or dull, conduct electricity and heat better than non-metals but not as well as metals, malleable and ductile
• Metals are able to conduct electricity a lot better than non-metals
• Unicellular organism


  Single-celled organism
• Multicellular organism


  Organism made up of many cells
• Protists (single-celled)


  • Can eat, move, excrete waste, reproduce
• Amoeba


  • Mostly present in ponds, slow-moving rivers and lakes, do not have a definite shape, have pseudopodia (finger-like projections) to assist in movement
• Paramecium


  • Live in aquatic habitats, typically oblong in shape, covered in hair-like structures called cilia which they use for locomotion
• Euglena


  • Present in freshwater and saltwater, have both animal and plant characteristics, produce food through photosynthesis
• All cells come from pre-existing cells
• Cell division


  The process by which a cell divides into two or more cells