General Chemistry

• Branch of physical science concerned with the composition, structure and properties of matter.

  Chemistry
• is any substance that has mass and takes up space by having volume

  Matter
• can be observed without changing the chemical composition of a substance

  physical properties
• can be observed due to the change in it's chemical composition

  chemical properties
• example of physical properties

  • temperature
  • boiling point
  • concentration
  • weight
  • length
• example of chemical properties

  • oxidation states
  • chemical bonding
  • coordination number
  • reactivity
  • toxicity
  • flammability
• classification of substances

  • pure substances
  • mixtures
• any matter that has fixed chemical composition and characteristic properties

  pure substance
• contain carbon, usually bonded to hydrogen

  organic compound
• usually don't contain carbon

  inorganic compound
• combination of two or more substances in variable proportions in which individual substances retain their identity

  mixtures
• distributed non uniformly

  heterogeneous mixture
• distributed uniformly

  homogeneous mixture
• we can't see the individual substances

  homogeneous
• we can see the individual substances

  heterogeneous
• small holes in the sieve let the sand particles through

  sieving
• separating the components of a suspension

  filtration
• solid particles are allowed to settled first at the bottom, and later the liquid which is called supernatant is poured into another container leaving behind solid particles

  decantation
• converting liquid to gas

  Evaporation
• separating a homogeneous mixture composed of two substances with different boiling point

  distillation
• is the process of separating elemental metals from other particles in a mixture

  magnetic separation
• is a process that can be used in extricating mixture that contain two substances with different melting points

  melting
• solid to gas

  sublimation
• mixture is poured into a special tube in the centrifuge apparatus

  centrifugation
• appeal to a large segment of the market or those that are routinely bought

  convenience product
• are the most common bleaching agents

  Na0Cl and H202
• can be measured by an instrument

  physical quantity
• are independent of each other and cannot be expressed in terms of one another

  fundamental
• can be expressed as combination of base quantities

  derived
• must be in terms of a. certain reference standard of measurement of that physical quantity

  units
• written technical information is effectively communicated, transcending the variation of language

  SI system
• metric system prefixes

  provides a simple way to understand exactly what each unit of measurement stands for in the metric system
• scientific notation 


  presenting very large numbers or very small numbers in a simpler form
• uncertainty

  lack of sureness
• uncertainty 


  indicates the range of values within which the measurement is asserted to lie woth some level of confidence
• absolute uncertainty 


  same unit as the quantity itself
• relative uncertainty 


  dimensionless and is obtained by dividing the absolute uncertainty by the numerical or measured value and multiplied by 100
• absolute uncertainty 


  shows how large the error is
• relative uncertainty 


  shows how large the error is in relation to the true value
• error

  the difference between the real value and the experimental value