Ch. 1 Chemistry: An Introduction What is chemistry

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Ch. 1Chemistry An Introduction

• What is chemistry?
• Chemistry is the study of the ___________________
  of substances and the
  changes they undergo.
• It began from _______________... the attempts
  of alchemists to change common metals into
  _________ through trial and error.
• Divisions of Chemistry
• There are several divisions or branches of
  chemistry
• 1) _________ chemistry the study of substances
  that contain ________
• Example how gasoline is produced from oil
• 2) _______________ chemistry the study of
  substances __________
• ___________
• Example how table salt reacts with different
  acids

composition
alchemy
gold
Organic
carbon
Inorganic
without
carbon
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Divisions of Chemistry (continued)

• 3) _______________ chemistry the study of the
  _______________ composition of substances
• Example how much chlorine is in a sample of
  tap water
• 4) ____________________ the study of the
  chemistry of _________ __________________
• Example how sugar in the blood stream of cats
  affect insulin production

Analytical
quantitative
Biochemistry
living
organisms
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The Scientific Method

• The scientific method is way to solve a
  scientific problem. It is an approach to a
  solution (using mostly common sense.)
• Example Your flashlight doesnt work. (Not
  necessarily a scientific problem.)
• Steps to the Scientific Method
• (1) Make _________________-- Use your 5 senses to
  gather information.
• (2) Propose a ______________-- Make an educated
  guess for what is happening.
• (3) Perform _______________-- This tests your
  hypothesis. Many experiments are sometimes
  needed to test a hypothesis. The same experiment
  must give similar results if the experiment is
  to be reliable.

observations
hypothesis
experiments
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Steps to the Scientific Method (continued)

• (4) Make a _____________-- This should explain
  the results of your experiments. Theories may
  ___________ or be ___________ over time because
  of results from new experiments.
• Scientific Laws
• Laws describe ____________ ___________________.
  
• A law tells what happens. It does not attempt to
  explain _____ the phenomena occurs. (That is the
  job of a theory.)
• Laws can often be summarized by a _____________
  __________.
• Example PV nRT (The _________ ______
  ______) This equation is used in Ch.
  12. The law shows the relationship
  between the pressure, volume and
  temperature of a given quantity of gas in a
  container.

theory
change
rejected
natural
phenomena
why
math
equation
Ideal Gas Law
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Chapter 2--Matter Change

• Matter vs. Mass
• Matter is anything that has _________ and takes
  up ___________.
• Examples ________, __________, and ________...
  (the three phases of matter)
• Things that are NOT matter __________, heat,
  ________, sound...
• Mass is the amount of ___________ in an object.
• The standard metric unit for mass is the
  ______________.

mass
space
solids
liquids
gases
light
emotions
matter
kilogram
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Plasma

• Plasma is a high energy electrically charged
  mixture of ions and electrons. __________ are
  made of plasma.
• While plasma is the most abundant phase of matter
  in the universe, on earth it only occurs in a few
  limited places
• Lightning bolts
• Flames
• Fluorescent lights
• Aurora Borealis (Northern Lights)

Stars
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Bose-Einstein Condensate

• Predicted in 1924 and created in 1995, the BEC is
  a small group of atoms clumped together when
  taken down to a few billionths of a degree above
  absolute zero.
• This group of atoms takes up the same place,
  creating a "super atom." There are no longer
  thousands of separate atoms.
• They all take on the same qualities and for our
  purposes become one blob.

Einstein
Bose
http//www.colorado.edu/physics/2000/bec/
400 nanoKelvins 200 nK 50 nK
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States of Matter
YES
YES
NO
NO
YES
NO
NO
NO
YES

• Particle Motion
• Solids-- particles ____________ back and forth in
  fixed positions
• Liquids-- clumps of particles ______ past each
  other in the container
• Gases-- individual particles _____ all over the
  place and collide
• _________ is a term used for a gaseous substance
  that is normally a ________ or _______ at room
  temperature.)
• Example _______ vapor

vibrate
slide
fly
Vapor
solid
liquid
water
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States of Matter
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Physical Properties and Physical Changes

• Physical properties can be determined/measured
  without changing the substances composition.
• Examples _______, odor, __________, mass,
  ________, _________ point, ____________
  point, hardness, solubility,
  etc.
• Physical Changes alter a substance without
  changing its composition.
• Examples crushing, ripping, breaking, and any
  _________ changes(boiling, freezing,
  melting, etc.)
• Most physical changes just alter the size of the
  particles and are usually reversible.

taste
color
density
melting
boiling
phase
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Physical Properties
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Physical Changes Names of the Phase Changes
Solid
Gas
Liquid
Solid?Aqueous ___________ Aqueous ?
Solid ___________
dissolving
crystallizing
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Mixtures

• Mixtures are a physical blend of two or more
  substances mixed together. The parts can be
  separated by _____________ means or ____________
  changes.
• There are 2 types of mixtures
• (1) _________________ Mixtures the parts mixed
  together can still be distinguished from one
  another...NOT uniform in composition.
• Examples chicken soup, fruit salad, _____,
  sand in water
• (2) _________________ Mixtures the parts mixed
  together cannot be distinguished from one
  another...completely uniform in composition.
• Examples ______, Kool-aid, ________, salt
  water, milk
• Another term for a homogeneous mixture is a
  ______________.

physical
physical
Heterogeneous
dirt
Homogeneous
Air
Brass
solution
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Heterogeneous Mixtures
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Homogeneous Mixtures
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Distillation

• One way to separate a _________ from a
  ___________ in a solution is by distillation.
  There are 2 steps to the process
• Step 1 _________ the solution.
• Step 2 ________________ the vapor as is escapes
  and collect it.
• Distillation Animation

solid
liquid
Boil
Condense
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Chemical Properties and Chemical Changes

• Chemical properties cannot be determined/measured
  without changing the substances composition
• Examples ____________, whether or not it
  reacts with an acid or a base.
• Chemical Changes
• Chemical changes will alter a substance and
  change its composition.
• Examples burning, ___________, rotting or
  decomposing,
  __________________, and other chemical
  reactions.
• Most, but not all, chemical changes are
  irreversible.
• You cant reverse the burning of paper.
• _____________ ____________ use a reversible
  chemical reaction

burning
rusting
fermenting
Rechargeable batteries
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Indications of Chemical Reactions
1) ________ is produced (________) 2)
________ is produced (_____________
bugs/_____________) 3) ______________ is
produced (______________)
matches
Heat
lightning
fireflies
Light
Electricity
batteries
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Indications of Chemical Reactions
4) ___________________ forms (_______
________) 5) gas/smoke/odor/bubbles
produced (________ ______)
soap scum
Precipitate
Two liquids chemically react to form a solid.
soda fizz
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Elements vs. Compounds

• An element cannot be ___________ down or
  _____________ into simpler substances by chemical
  means.
• Elements are the _________ forms of matter that
  can exists in normal laboratory conditions.
• Examples _______, Helium, __________
• A compound is made up of ____ or ________
  different elements ______________ bonded
  together.
• Compounds can only be broken down into simpler
  substances by ____________ ____________.
• Examples _______, Sand, _______________

broken
changed
simplest
Mercury
Gold
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more
chemically
chemical reactions
Water
NaCl (table salt)
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Classification of Matter
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Classification of Matter
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Classification of Matter
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Chemical Symbols

• Chemists use chemical symbols for the elements
  involved in a chemical reaction. The symbols are
  a shorthand way of representing the
  ______________. (See the Periodic Table for a
  list of all the symbols.)
• The first letter of the chemical symbol for an
  element is always _________________.
• The next letter, if needed, is _______________.
  Each capital letter in a formula, therefore,
  represents another element.
• Examples ____, ____, Hg, ___, NaBr, ________,
  LiC2H3O2
• Some symbols come from _______ names AuAurum
  (Gold)

elements
capitalized
lowercase
H
Ne
S
H2O
Latin
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Chemical Reactions

• When writing chemical reactions, the substances
  that ___________ with each other are written on
  the _______ and are called reactants.
• The substances that are ____________ are written
  on the _______ and are called the products.
• Reactants ? Products
• The ? symbol can be read as _______ or
  reacts to produce.
• Example 2H2 O2 ? 2H2O
• which means ____________________________________
  
• ________________________________________________.
  

react
left
produced
right
yields
two hydrogen molecules
plus one oxygen
molecule
yields
two water molecules
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Conservation of Mass

• During chemical (or physical) reactions, mass (or
  matter) is neither _____________ nor
  _________________.
• The mass of all the reactants _________ the mass
  of all the products.
• The ___________ of each kind of atom is the same.
• Sometimes it appears that the reactant and
  product masses are not equal, but a _______ was
  probably a reactant or product in the reaction,
  and that is making the difference!
• Example 2H2 O2 ? 2H2O
• If 4 grams of hydrogen reacted with oxygen to
  produce 36 grams of water, how many grams of
  oxygen were used? _______
• Notice that the ____ of Hs and Os on each side
  is __________!

created
destroyed
equals
number
gas
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constant
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Conservation of Mass
CaCl2 Na2SO4 ? CaSO4 2NaCl
mass before mass after atoms before atoms
after