Physical and Chemical Changes of Matter

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Physical and Chemical Changes of Matter

• Wolfarth, Barham, Hinton, and Reed

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VOCABULARY for MATTER AND CHANGES IN MATTER

• Thermal Energy- Every substance contains energy
  from the movement of its particles, called
  thermal energy.
• Chemical energy- another form of energy that
  comes from the chemical bonds within matter
• Law of conservation of Energy- Matter changes
  whenever energy is added or taken away. In every
  physical and chemical change, the total amount of
  energy stays the same.
• Characteristic property- is a property that
  always holds true for a substance.
• Since, for a given substance, characteristic
  properties never change, they can be used to
  identify unknown matter.

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VOCABULARY for MATTER AND CHANGES IN MATTER

• Boiling Point- is a temperature at which a liquid
  boils (characteristic property)
• Melting Point- is the temperature at which a
  solid melts, or turns to liquid (characteristic
  property)
• Vaporization- occurs when a liquid gains enough
  energy to become a gas
• Evaporation- When vaporization takes place only
  on a liquid surface, the process is called
  evaporation
• Condensation- The opposite of vaporization, which
  occurs when a gases loses enough thermal energy
  to become a liquid
• Sublimation- occurs when the surface particles of
  a solid gain enough energy to become a gas. In
  sublimation, particles do not pass through the
  liquid state.

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VOCABULARY for MATTER AND CHANGES IN MATTER

• Physical Change- A change that alters the form or
  appearance of a material or does not convert the
  material into a new substance
• Chemical Change- a change in matter that forms
  one or more new substances
• Chemical Activity- The ability of a substance to
  undergo a chemical change
• Chemical reaction- a chemical change or chemical
  reaction, is like scrambling the letters of a
  word to make new words
• Mixture- consists of two or more pure
  substances-elements, compounds or both that are
  in the same place but are not chemically
  combined.
• Solution is a well-mixed mixture, such as salt
  and water
• Precipitate a solid that forms a solution
  during a chemical reaction

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VOCABULARY MATTER AND CHANGES IN MATTER

• Pure substance- is made of only one kind of
  material and has definite properties.
• Elements- are pure substances that cannot be
  broken down into other substances by any chemical
  means. Elements can chemically combine in many
  different ways to form a huge variety of
  compounds.
• Compound- is a pure substance formed from
  chemical combinations of two or more different
  elements. Compounds always have properties
  different from the elements that formed them
  (Water is an example)
• Atom- The smallest particle of an element
• Molecule- a particle made of two or more atoms
  bonded together
• Chemical bond- the forces that hold atoms
  together
• Chemistry- is the study of properties of matter
  and how matter changes

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MATTER AND CHANGES IN MATTER

• All of the matter around is composed of one
  element or a combination of two or more elements.
• An element is a substance that cannot be broken
  down into any other substances by chemical or
  physical means.
• A compound is a substance made of two or more
  elements chemically combined in a specific ratio,
  or proportion. Compounds have different
  properties than the elements that form them.
• A molecule is a particle made of two or more
  atoms bonded together. Some molecules are made of
  atoms that are all alike, as in the oxygen gas
  (O2) that you breathe.

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Molecules may be as simple as oxygen. Or, they
may be as complex as DNA in living cells.
However, all molecules are made of atoms.
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VOCABULARYFROM THE LIST BELOW, CHOOSE THE TERM
THAT BEST FITS THE SENTENCE
Chemical energy melting law of
conservation of energy sublimation Thermal
energy freezing vaporization
chemical reaction Evaporation
boiling
condensation

• The higher the temperature of something, the
  greater its____________________.
• The change of state from gas to liquid is called
  _______________.
• Energy that comes from bonds within matter is
  called_________.
• The change in state from liquid to gas is
  called________________.
• Gas bubbles forming throughout a liquid is
  called_____________.
• Liquid changing to gas only at the surface is
  called ___________.
• The change of state from solid to liquid is
  called______________.
• The change of state from Liquid to solid is
  called______________.
• The _________states that during any change, that
  the amount of energy stays the same.
• Another terms for chemical change is
  _______________________.
• In ____________, particles pass directly from
  solid to gas.

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VOCABULARYFROM THE LIST BELOW, CHOOSE THE TERM
THAT BEST FITS THE SENTENCE
Chemical energy melting law of
conservation of energy sublimation Thermal
energy freezing vaporization
chemical reaction Evaporation
boiling
condensation

• The higher the temperature of something, the
  greater its _thermal energy_.
• The change of state from gas to liquid is called
  _condensation__.
• Energy that comes from bonds within matter is
  called chemical energy_.
• The change in state from liquid to gas is called
  vaporization_.
• Gas bubbles forming throughout a liquid is called
  boiling_.
• Liquid changing to gas only at the surface is
  called evaporation.
• The change of state from solid to liquid is
  called _melting_.
• The change of state from Liquid to solid is
  called _freezing_.
• The law of conservation of energy states that
  during any change, that the amount of energy
  stays the same.
• Another terms for chemical change is chemical
  reaction_.
• In _sublimation_, particles pass directly from
  solid to gas.

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Describing Matter
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Describing Matter

• Matter can change properties. For example, water
  is a liquid at room temperature, a solid at cold
  temperatures, and an invisible gas at high
  temperatures.
• Solids, liquids and gases are the three
  principles states of matter.

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Examples of Common Solutions
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Every substance contains energy from the movement
of its particles, called thermal energy. The
higher the temperature of a substance, the
greater its thermal energy. Another form of
energy comes from the chemical bonds within
matter. This form of energy is called chemical
energy.
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Matter changes whenever energy is added or taken
away. In every physical and chemical change, the
total amount of energy stays the same. This
principle is called the Law of Conservation of
Energy.
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Under certain conditions, a substance can change
from any one state of matter to any other.
Changes of state are physical changes.
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The change of state from solid to liquid is
called melting.
In most pure substances, melting occurs at a
specific temperature called the melting point. As
a solid absorbs thermal energy, its molecules
vibrate faster. If its molecules vibrate fast
enough, they break free from each other. The
solid becomes a liquid.
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Freezing is the change of state from liquid to
solid.
Molecules of a liquid slow down when they lose
thermal energy. If the molecules slow down
enough, they begin to form regular patterns. The
liquid becomes a solid.
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Liquid water changing into water vapor is an
example of vaporization. Vaporization occurs when
a liquid gains enough energy to become a gas.
When vaporization takes place only on a liquids
surface, the process is called evaporation. When
vaporization takes place throughout a liquid, the
process is called boiling.
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The opposite of vaporization is called
condensation, which occurs when a gas loses
enough thermal energy to become a liquid. The
change of state from gas to liquid is called
condensation.
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Sublimation occurs when the surface particles of
a solid gain enough energy to become a gas. In
sublimation, particles do not pass through the
liquid state.
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PHYSICAL AND CHEMICAL CHANGES

• Understanding Main Ideas
• Check the type of change or changes that apply to
  each description.

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PHYSICAL AND CHEMICAL CHANGES

• Understanding Main Ideas
• Check the type of change or changes that apply to
  each description.

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Plants make chlorophyll in the plants leaves.
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The color changes in autumn leaves are due, in
part, to the cessation of a chemical reaction.
The plants stop making chlorophyll while existing
chlorophyll is breaking down. The brilliant
colors of fall foliage result when green
chlorophyll in leaves breaks down. The colors of
other substances in the leaves become visible.
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Chemical changes or chemical reactions, also
involve energy. In chemical reactions, new
chemicals are produced, either when two or more
substances combine or substances break down.
Chemical reactions either absorb energy or
release energy.
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The copper-covered Statue of Liberty has stood in
upper New York Bay for more than a 100 years. The
green color of the Statue of Liberty comes from a
change to the statues copper metal covering.
These changes are a result from chemical
reactions.
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Wood cut down into logs is a physical change
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The strike of a match is a chemical change due to
the reaction of the chemicals with oxygen.
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Burning woods turns to charcoal and ashes. This
is a chemical change.
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Answer the following on a separate sheet of paper.

• Compare the total amount of energy before and
  after physical and chemical changes.
• Can energy be released during a chemical
  reaction? Can it be absorbed? Can a chemical
  reaction take place in which energy is neither
  absorbed or released?

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Answer the following on a separate sheet of paper.

• Compare the total amount of energy before and
  after physical and chemical changes. In every
  physical and chemical change, the total amount of
  energy stays the same.
• Can energy be released during a chemical
  reaction? Yes Can it be absorbed? Yes Can a
  chemical reaction take place in which energy is
  neither absorbed or released? No

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Building VocabularyGive an example of each of
the terms below. Write your answer on the line
next to the term.

• An element ____________________
  
• A pure substance ____________________
• A mixture ____________________
• A solution ____________________
• A compound ____________________

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Building VocabularyGive an example of each of
the terms below. Write your answer on the line
next to the term.

• An element carbon, oxygen and
  hydrogen
• A pure substance sugar, salt, and iron
• A mixture salt water, soil, beach
  sand, and OJ
• A solution sugar water and salt
  water
• A compound water, carbon dioxide,
  sugar

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HmmI remember in lab shaping the play dough into
different forms was a physical change!
And I remember that when the cake batter reacts
with oxygen in the oven and bakes into a cake, it
is a chemical reactiona new substance has formed!
The End