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					                                                                                 Accelerated Chemistry
                                                       Chapter 1 Notes – Matter, Energy and Change
                                                                  Chemist: ____________________
Chapter 1 problem set:
Reviewing concept 5, 7-11, 13-19, 21, 22; problems 1, 3, 4


1.1 What is Chemistry?
       the study of matter and its transformations



Why Study Chemistry?
       learn fundamental physical models

       gain technical perspective on current events

       develop problem solving skills

       appreciate life's little mysteries

Most of the building materials, clothes, and medicines today are the result of chemistry

Branches of Chemistry
       organic –the study of the structures, synthesis, and reactions of carbon- compounds



       inorganic – the study of the properties and reactions of inorganic compounds



       physical - dealing with the physical properties of chemical substances



       biochemistry - study of the chemistry of living things



       analytical - analysis of material samples to gain an understanding of their chemical composition
        and structure.




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                                                                             Accelerated Chemistry
                                                  Chapter 1 Notes – Matter, Energy and Change
1.2 Matter and Energy
Matter
Matter – anything that has mass and occupies space


Inertia – the tendency of a body to stay at rest or to continue to move at the same velocity,
unless acted on by an outside force. A tractor trailer has more inertia than a bicycle. A
bowling ball has more inertia than a tennis ball.


Mass and weight – used interchangeably, but there is a difference…


        Mass – a quantity of matter, mass is measured using a balance


        Weight - a measure of gravity's effect on something; use a scale to measure weight

Law of Conservation of Mass
        Matter can neither be created nor destroyed in chemical or physical changes.

        Example – sodium metal + chlorine gas ---> table salt, an edible crystal

Energy
Everything that you see or sense is either matter or the interactions of energy and matter.
True or False?
Ex: a book – a chunk of matter – hold it up – potential energy – drop it – kinetic energy


Energy – the ability to cause change or the ability to do work. (two types)


        Kinetic –the energy of motion

                         Ex. baseball in flight, car rolling down a street

        Potential – stored energy waiting to be released                      Car transparency
                                                                               (figure 1-9)
                         Ex: gasoline, water behind a dam

Law of conservation of energy –
        Energy can change forms, but it cannot be created or destroyed by ordinary
         chemical or physical changes

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                                                                            Accelerated Chemistry
                                                     Chapter 1 Notes – Matter, Energy and Change
1.3 States of Matter
               Gas                                 Liquid                        Solid




       low density                           high density                high density

       easy to                               hard to                     hard to
        expand/compress                        expand/compress              expand/compress

       shape - fills container               takes shape of              rigid shape
                                               container
       quick diffusion                                                    low diffusion
                                              middle diffusion
       volume – container                                                 definite volume
                                              definite volume




Plasma – A highly ionized gas. The fourth state of matter (it does matter). 99% of all matter
in the universe is in a plasma state. Lightning, neon lights and fire are natural examples of
plasma on Earth.


Plasma tv’s? What are they all about?
Plasma in flat-panel display technology that ignites small pockets of gas to light
phosphors. Each plasma panel contains thousands of tiny tubes filled with ionized gas that,
when excited by electricity, glow in different colors and intensities to create an image.




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                                                                         Accelerated Chemistry
                                                    Chapter 1 Notes – Matter, Energy and Change
Properties and Changes of Matter
Properties – characteristics that enable us to distinguish one kind of matter from another
       describe materials by listing their properties

Chemical properties vs. physical properties
       Measurement of a chemical property involves a chemical change.

       Ex: determining the flammability of gasoline involves burning it, producing CO 2 and
        H2O; wood burning, rusting iron, tarnishing silver, leaves changing colors, baking a
        cake



       Measurement of a physical property may change the arrangement but not the
        structure of the molecules of a material.

       Ex: density, color, boiling point, volume, temperature, and mass.

Intensive properties vs. extensive properties

       Extensive properties change when sample size changes; intensive properties don't.




                                   Mass of water           100.0 g               10.0 g

                                 Volume of water           0.100 L               0.010 L

                          Temperature of water              25 °C                 25 °C

                                 Density of water         1.00 g/mL             1.00 g/mL




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                                                                    Accelerated Chemistry
                                             Chapter 1 Notes – Matter, Energy and Change

Chemical change vs. physical change
       A chemical change occurs when a substance is converted into a different
        substance

       Ex. chemical change: sodium metal + chlorine nonmetal --> table salt (crystal,
        white, edible)

       Ex. physical change: cutting paper, chopping wood, freezing water

Signs of a chemical change
       evolution of heat and light

       production of a gas

       formation of a precipitate




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                                                                                      Accelerated Chemistry
                                                        Chapter 1 Notes – Matter, Energy and Change

Energy and Changes in Matter - Chemical reactions involve energy
                    Exothermic                                                  Endothermic

         releases energy                                         absorbs energy

         reactants --> products + heat                           reactants + heat ---> products

         water(l) →          ice(s) + heat                       ice(s) + heat → wate(l)

         Graph:                                                  Graph


          Water (reactants)

                                                                                          Water (products)
 Energy
                                heat

                                                                         heat
                                                          Energy
                                       Ice (products)




                                                                    ice (reactants)



   Examples of exothermic processes                        Examples of endothermic processes

making ice cubes                                         melting ice cubes
formation of snow in clouds                              conversion of frost to water vapor
condensation of rain from water vapor                    evaporation of water
a candle flame                                           forming a cation from an atom in the gas
                                                         phase
mixing sodium sulfite and bleach                         baking bread
rusting iron                                             cooking an egg
burning sugar                                            producing sugar by photosynthesis
forming ion pairs                                        separating ion pairs
combining atoms to make a gas molecule                   splitting a gas molecule apart
mixing strong acids and water                            mixing water and ammonium nitrate
nuclear fission                                          melting solid salts




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                                                                         Accelerated Chemistry
                                                 Chapter 1 Notes – Matter, Energy and Change
1.4 Classification of Matter



                                                    Matter




                          Mixtures            Separate physically        Pure Substances




 Heterogeneous                             Homogeneous             Compounds             Elements



                                                                       Separate chemically


   Suspension                    Solution                Colloid




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                                                                            Accelerated Chemistry
                                                 Chapter 1 Notes – Matter, Energy and Change

                    Mixture                                           Pure Substance
   combination of two or more kinds of                    homogeneous sample of matter that
    matter, but each retains its own physical               always has the same composition
    properties                                                          Compound
              Heterogeneous                                substance that can be decomposed
    composition is not uniform where                       into 2 or more substances by
    samples are different; salad or                         chemical change
    vegetable soup                                          Ex: NaCl, H2O, C6 H12O6, CO2




              Homogeneous                                                Element
   Uniform composition; every sample is                   substance that cannot be broken
    the same; air, salt water, sugar water                  down by ordinary chemical change
                                                           Ex: Au, Cu, Ni, Na



                Suspension
   Solid in liquid
   muddy water, granite
                   Solution
   small particles that won’t scatter light
   ex: air, salt water
                    Colloid
   particles larger than molecules, scatter
    light
   Shaving cream, starch water


Side note: the Law of Definite Composition states that when a compound breaks down, it always
gives the same proportion of its constituent elements (Joseph Proust – 1799)

Ex – sugar (C 6H12O6) always consists of 42.1% C, 6.5 % H, 51.4 % O

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                                                                      Accelerated Chemistry
                                               Chapter 1 Notes – Matter, Energy and Change
1.5 The Chemical Elements
       The periodic table compactly shows relationships between elements, and features
        are:

            o    Periods are horizontal rows on the table.

            o    Groups (or families) are columns on the table.

                        elements in the same group have similar chemical properties.

            o    Blocks are regions on the table.




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                                                                        Accelerated Chemistry
                                                  Chapter 1 Notes – Matter, Energy and Change




            o    alkali metals (Group IA, first column )
                        soft, extremely reactive metals
                        react with cold water to form hydrogen gas
                        form +1 ions
            o    alkaline earth metals (Group IIA, second column):
                        soft, reactive metals
                        compounds are a major component of earth's crust
                        form +2 ions
            o    halogens (Group VIIA, next-to-last column):
                        poisonous and extremely reactive nonmetals
                        fluorine and chlorine are yellow-green gases
                        bromine is a volatile red-brown liquid
                        iodine is a volatile blue black solid
                        all form -1 ions
            o    noble gases (Group 0, last column)
                        all are monatomic gases

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                                                                       Accelerated Chemistry
                                                  Chapter 1 Notes – Matter, Energy and Change
                        a. k. a. inert gases; almost completely unreactive




            o    Transition metals are the elements in the 3rd to 12th columns.

                        hard, dense metals

                        less reactive than Group IA and IIA

            o    Rare earth metals are the elements at the bottom of the table.

                        lanthanides (annex, top row)

                        actinides (annex, bottom row)

            o    Main group elements are all elements (except transition and rare earth).

                        group numbers end with "A"

            o    Metals, nonmetals, and metalloids (semimetals)

                        lustrous

                        malleable: can be hammered into thin sheets

                        ductile: can be drawn into wire
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                                                                     Accelerated Chemistry
                                                Chapter 1 Notes – Matter, Energy and Change
                        conduct heat and electricity well




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