Welcome to Chemistry!!

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Welcome to Chemistry!!
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What is Chemistry?

• The study of all substances composition,
  structure and properties - and the changes that
  they can undergo.
• Chemistry is everything!!

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Branches of Chemistry

• CHEMISTRY

Biological
Organic
Inorganic
Physical
Analytical
Theoretical
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Types of Research

• Basic for the sake of increasing knowledge
• Applied generally used to solve a problem
• Technological Development production/use of
  products to improve quality of life

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What is Matter?

• Matter is anything that has mass and takes up
  space.
• Mass is the amount of matter in an object.

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Building Blocks of Matter

• Atom smallest unit of an element that maintains
  the chemical identity of that element
• Element pure substance, all one type of atom
• Compound made of atoms of two or more elements
  chemically bonded

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Properties

• Extensive depend on amount of matter
• Ex volume, mass
• Intensive do not depend on amount of matter
• Ex melting and boiling point, density

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Physical Properties

• Physical Property- a property that can be
  observed and measured without changing the
  substance.
• Physical change - changes appearances, without
  changing the composition.

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States of Matter

• Solid- has definite shape and definite volume.
• Liquid- definite volume but takes the shape of
  its container (flows).
• Gas- a substance without definite volume or shape
  and can flow.
• Plasma- high temperature state of matter where
  atoms lose most of their electrons

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States of Matter
Definite Volume?
Definite Shape?
Temp. increase
Com-pressible?
Small Expans.
Solid
YES
YES
NO
Small Expans.
Liquid
NO
NO
YES
Large Expans.
Gas
NO
NO
YES
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Liquid
Gas
Solid
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Chemical Properties

• Chemical Property- a property that can only be
  observed by changing the type of substance.
• Examples Flammability, decomposition, reactivity
• Chemical change/reaction - a change where a new
  form of matter is formed.

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Chemical Reactions

• Reactants substances that react
• Products substances that are formed
• Paper Oxygen Fire ? Ash Smoke

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Classification of Matter
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MATTER
Can it be separated?
no
yes
Pure Substances
Mixtures
Is composition uniform?
Can it be decomposed by ordinary chemical means?
no
yes
no
yes
Homogeneous Mixture Air, sugar water, stainless
steel
Heterogeneous Mixture Granite, wood, blood
Compounds Water, sodium chloride
Elements Gold, aluminum
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Mixtures

• Blend of two or more kinds of matter, each of
  which retains its own identity and properties
• Heterogeneous- mixture is not the same from place
  to place.
• Chocolate chip cookie, gravel, soil.
• VISIBLE particles
• Homogeneous- same composition throughout. aka
  solution
• Kool-aid, air.
• NON-VISIBLE particles

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Separating Mixtures

• Heterogeneous mixtures use filtration or
  vaporization
• Homogeneous CANNOT use filtration
• - use distillation, crystallization and
  chromatography

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Distillation
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Chromatography
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Pure Substances

• Either Compounds or Elements
• Every sample has exactly same characteristic
  properties (mixtures depend on components)
• Every sample has exactly same composition ALWAYS

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Which is it?
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MATTER
Can it be separated?
no
yes
Pure Substances
Mixtures
Is composition uniform?
Can it be decomposed by ordinary chemical means?
no
yes
no
yes
Homogeneous Mixture Air, sugar water, stainless
steel
Heterogeneous Mixture Granite, wood, blood
Compounds Water, sodium chloride
Elements Gold, aluminum
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Elements
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Periodic Table

• Elements are organized into groups based on
  similar chemical properties
• Vertical columns Groups/Families
• Horizontal rows Periods
• 2 rows on the bottom
• Lanthanide series
• Actinide series

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Types of Elements
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Metals
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Metals

• Conduct electricity and heat
• Malleable hammered into sheets
• Ductile drawn into wire
• Tensile strength resist breaking when pulled

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Nonmetals
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Metalloids
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Types of Elements

• Nonmetals
• Poor conductor of heat and electricity
• Solids are brittle
• Metalloid
• Share characteristics of metals and nonmetals
• semiconductors
• Noble Gases relatively unreactive