Chemistry What is Chemistry?

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Chemistry What is Chemistry?

• Chemistry is the central science. It is the
  study of the composition, the structure, the
  properties, and the reactions of matter.
• The composition the parts----how it is made up
• The structure how the parts are arranged and
  put together
• The properties physical and chemical
• Matter Anything that has mass and occupies
  space (VOLUME)
• In other words ---STUFF
• Chemistry is the study of stuff

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Divisions of Chemistry

• Inorganic Chemistry-
• -the chemistry of everything except carbon
• -of the approx. 4 million chemicals -100,00 of
  those are inorganic
• Organic
• The study of carbon (along with hydrogen)
• 3. Analytical Chemistry, Biochemistry, Physical
  Chemistry, and Nuclear Chemistry

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Whats ah Matter huh?

• Matter -anything that has mass (the amount of
  matter in an object) and volume (the amount of
  space an object takes up)
• Atoms- the basic building block of all matter.
  The various combinations of these atoms make
  up everything we touch, hear, taste, and smell.
• Molecules- are combinations of atoms. They
  may be small and simple Cl2, or extremely
  complex containing thousands of atoms.

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Properties of Matter

• Physical Vs. -Chemical
• Physical Properties- anything that can be
  observed or measured without destroying the
  substance.
• Ex. Texture, color, state, mass, volume,
  density, melting point, boiling point,
  conductivity..
• Chemical Properties- can only observed when
  substances interact with one another.
• Ex. Flammability, reactivity with acid,
  reaction with oxygen
• Intensive properties- do not depend on the amount
  of a substance
• ex. Color, texture, density.
• Extensive properties- do depend on the amount of
  a substance
• ex. mass, volume

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Matter Continued

• Physical changes-Vs.- Chemical changes
• Physical change- A change in which the identity
  of the substance doesnt change
• Ex. Changes of state, sugar dissolved in water,
  crushing a rock, etc.
• Chemical Change- The identity of the substance
  changes and a new substances form
• Ex. Rust, vinegar and baking soda, etc..
• Evidence of a Chemical Change
• Evolution of a gas
• Formation of a precipitate (ppt.)
• Change of energy
• Change in temperature
• Giving off light
• Color change

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Classification of Matter
Matter
Pure substance Mixtures Cannot be separated
by Can be separated by physical means
physical means ex. H2O, Fe, Cl2, C22H38O9 ex.
Dirt, ink, blood, salt water
element compound
homogenous heterogeneous made up of
only made up of more
composition is composition isnt one
kind of atom than one kind of
atom uniform uniform ex. Fe,
ex. H2O ex. Soda pop, ex.
Salad, your class Cl2 C4H10O
air, salt water tacos,
blood
There are several elements that exist as DIATOMIC
elements H2 O2 F2 Br2 I2
N2 Cl2 (HOFBrINCl)