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Atoms

  • Smallest particle of matter
  • Made up of subatomic particles
  • Has a nucleus, containing protons and neutrons
  • Has electrons in orbits around the nucleus
  • Matter can’t be created or destroyed only changed

Molecules

  • Atoms can form chemical bonds(attracted and stuck to each other)
  • 2 or more atoms chemically bounded is called a molecule
  • Atoms of the same element can bond together
  • Atoms of different elements can bond together

Elements

  • Made up of one type of atom
  • All their atoms are the same
  • Cannot be broken down into anything simpler
  • 118 elements
  • 94 are naturally occurring, others are artificial
  • Found on periodic table
  • Can be made up of molecules
  • Has a chemical system

Compound

  • is made up of more than 1 element
  • Described by a chemical formula
  • States which atoms are in one unit of the compound
  • Not all are made up of molecules, but many are.

Mixtures

  • Solute is a substance that is dissolved in a solution
  • Pure substances
    • Elements and compound-Cant be split into anything simpler
    • Has a unique feature
    • Always have the same physical properties
    • Always have the same chemical properties

Impure substances

  • Mixtures
  • Can be physically separated
  • Properties are an average of the properties of the ingredients
  • Physical properties depend on the proportion of each substance in the mixture
  • Melting and boiling points and density depend on the ratio of the ingredients
  • Chemical reactivity can vary, depending on mixture and particle size

Homogeneous

  • Particles are evenly distributed
  • Aqueous solution is when there is a homogeneous liquid with something dissolved in it
  • Can be mixture, element or compound
  • Only one state of matter
  • Are uniform and consistent throughout

Heterogeneous

  • Particles are not evenly distributed
  • All must be a mixture
  • Not uniform throughout
  • Can see separate ingredients
  • Can be in different states of matter

Solution

  • Form when one material dissolves in another
  • Is homogenous
  • Substance that dissolves is a solute
  • Substance that dissolves the solute is a solvent
  • Is transparent
  • Solute is split up into tiny particles, evenly distributed through the solvent, which ae too small to see(even under a microscope)
  • Not all substances dissolve well in a solvent.
  • Substances that dissolve well are soluble
  • Substances that don’t dissolve well are insoluble
  • Substances might be insoluble in water but soluble in a different solvent

Suspension

  • Formed when an insoluble solid mixes with a liquid and does not dissolve
  • Are heterogenous
  • Particles of the solid are quite large and visible
  • Makes it opaque
  • Particles of the solid will settle to the bottom over time
  • Suspensions are separated by filtration

Colloids

  • Between solutions and suspensions
  • Homogeneous
  • Particles are not dissolved
  • Particles are smaller than suspensions, so do not settle at all, but stay mixed
  • Particles scatter light
  • Opaque
  • a homogeneous non-crystalline substance consisting of large molecules or ultramicroscopic particles of one substance dispersed through a second substance. Colloids include gels, sols, and emulsions; the particles do not settle, and cannot be separated out by ordinary filtering or centrifuging like those in a suspension.

Emulsions

  •  Fine dispersion of minute droplets of one liquid in another in which it is not soluble or miscible
  • Opaque
  • Heterogenous
  • E.g. egg yolk, butter, oil and water
Miscible: Forms a homogeneous mixture when added together with another miscible
Matter: anything that has volume or weight
Weight: Gravity’s pull on mass
Mass: Space occupied by object