Unit 1: Matter

• matter - anything that occupies space and has mass
• mass - amount of substance
• weight - refers to the downward pull of object towards the center of the earth
• physical properties - can be observed and measured without changing the substance
• chemical properties - can be observed by changing the type of substance
• extensive properties - depends on the amount of matter
• intensive properties - depends on the type of matter, not the amount of
• pure substance - made up of only one kind of matter and possess definite, fixed, and unvarying composition with unique set of properties
• Pure substance:

  1. Elements
  2. Compounds
• elements - simplest form of substance, cannot be decomposed by simple chemical means, and building blocks of matter
• Elements:

  1. Metal
  2. Non-metals
  3. Metalloids
• compounds - substances that are made up of molecules with two or more kinds of atoms in definite proportions
• Compounds (according to bonds):

  1. Ionic
  2. Covalent
  3. Metallic
• ionic - electron transfer
• covalent - electron sharing
• metallic - interaction between metallic elements
• Compounds (according to composition):

  1. organic
  2. inorganic
• organic - carbon compounds
• Inorganic compounds:

  1. Acids
  2. Bases
  3. Salts
  4. Oxides
• acids - contain hydrogen, yields hydrogen ions in water solutions
• bases - contains a metal with hydroxyl group
• salts - combined positive and negative ions
• oxides - oxygen and other element
• mixtures - contain two or more substances
• Mixtures (according to appearance):

  1. Homogeneous
  2. Heterogeneous
• homogeneous - uniform appearance, has the same properties and composition thoughout
• heterogeneous - two or more distinct portions, different properties and composition
• Mixtures (according to particle size):

  1. Solution
  2. Colloid
  3. Suspension
• solution - molecular size; solute and solvent
• colloid - 10,000 angstrom; dispersing phase an dispersion medium
• suspension - larger than 10,000 angstrom
• Separation methods:

  1. Filtration
  2. Distillation
  3. Magnetic separation
  4. Decantation
  5. Sublimation
• filtration - separation of a solid from liquid in a heterogeneous mixture using a filtering membrane
• distillation - separation of liquids in a homogeneous mixture
• magnetic separation - separation of a magnetic solid from a heterogeneous mixture
• decantation - separation of a solid from a liquid in a heterogeneous mixture based on gravity
• sublimation - separation of a volatile solid from a non-volatile solid
• physical - change in physical properties without changing its chemical composition, no new product, temporary, reversible, no change in mass
• Physical change:

  1. evaporation
  2. condensation
  3. melting
  4. freezing
  5. sublimation
  6. deposition
• chemical - change in its chemical composition and constitution of the substance, new product is formed, permanent, irreversible, change in mass