Chapter 4 Chapter 4 notes notes • I. GREEK THEORY I. GREEK THEORY • A. DEMOCRTUS- The universe is made of A. DEMOCRTUS- The universe is made of indivisible pieces of matter called atoms indivisible pieces of matter called atoms • 1. atom- Greek for unable to divide 1. atom- Greek for unable to divide • 2. Not able to explain all 2. Not able to explain all observations though and was dismissed observations though and was dismissed • II DALTON’S THEORY II DALTON’S THEORY • A. Every element is made of tiny unique A. Every element is made of tiny unique particles called atoms and cannot be subdivided particles called atoms and cannot be subdivided • B. atoms of the same element are exactly B. atoms of the same element are exactly alike alike • C. atoms of different elements can join C. atoms of different elements can join to form molecules to form molecules
Transcript
Chapter 4 Chapter 4 notesnotes
• I. GREEK THEORYI. GREEK THEORY• A. DEMOCRTUS- The universe is made of A. DEMOCRTUS- The universe is made of
indivisible pieces of matter called atomsindivisible pieces of matter called atoms• 1. atom- Greek for unable to divide1. atom- Greek for unable to divide• 2. Not able to explain all observations 2. Not able to explain all observations
though and was dismissedthough and was dismissed• II DALTON’S THEORYII DALTON’S THEORY• A. Every element is made of tiny unique A. Every element is made of tiny unique
particles called atoms and cannot be subdividedparticles called atoms and cannot be subdivided• B. atoms of the same element are exactly alikeB. atoms of the same element are exactly alike• C. atoms of different elements can join to form C. atoms of different elements can join to form
moleculesmolecules
• III ATOMIC THEORYIII ATOMIC THEORY• A. Nucleus- The center of the atom with a positive chargeA. Nucleus- The center of the atom with a positive charge• 1. Protons- positively charged particle in the nucleus with an atomic 1. Protons- positively charged particle in the nucleus with an atomic
mass of 1AMU( ATOMIC MASS UNIT)mass of 1AMU( ATOMIC MASS UNIT)• 2. Neutrons- The neutral charged particle of the nucleus having the 2. Neutrons- The neutral charged particle of the nucleus having the
mass of 1 amumass of 1 amu• B. Electron cloud- The region around the nucleus with a negative B. Electron cloud- The region around the nucleus with a negative
• B.Ruherford’s gold foil experimentB.Ruherford’s gold foil experiment• 1.Hypothesis- the atom is solid and 1.Hypothesis- the atom is solid and
the particles will bounce offthe particles will bounce off• 2.Observations- most of the particles 2.Observations- most of the particles
went straight through, except once in a went straight through, except once in a while one would bounce backwhile one would bounce back
• 3.New conclusions- the atom is 3.New conclusions- the atom is mostly empty except it has a dense coremostly empty except it has a dense core
• IV. MODELS OF THE ATOMIV. MODELS OF THE ATOM• A. BOHR’S MODEL- An explanation of electron A. BOHR’S MODEL- An explanation of electron
movement about the nucleusmovement about the nucleus• 1. Suggested energy levels1. Suggested energy levels• a. energy levels- any of the possible a. energy levels- any of the possible
energies an electron can have in the atom. Level 1= energies an electron can have in the atom. Level 1= 2 e: 2 e:
• level 2=8e: level 3= 18e: level 4=32: level 5=50level 2=8e: level 3= 18e: level 4=32: level 5=50• 1. electrons gain energy to move to a 1. electrons gain energy to move to a
higher level and give up energy when they drop back higher level and give up energy when they drop back into a lower level( ground state) into a lower level( ground state)
• 1. No longer assumed the electron moved in definite 1. No longer assumed the electron moved in definite orbitals( Heisenberg uncertainty principle)orbitals( Heisenberg uncertainty principle)
• B. NEW VIEW OF BOHR’S MODELB. NEW VIEW OF BOHR’S MODEL
• 1. Electrons behaves more like waves1. Electrons behaves more like waves
• 2. spinning fan image- Cannot locate 2. spinning fan image- Cannot locate the location of the fan blade at any time, the location of the fan blade at any time, just know it’s in the blurjust know it’s in the blur
• a. same applies to an electron,- a. same applies to an electron,- The best we can do is give the probable The best we can do is give the probable location of the electron.location of the electron.
• C. ENERGY LEVELS OF ELECTRONSC. ENERGY LEVELS OF ELECTRONS• 1. Orbital- the region where there is a high probability of 1. Orbital- the region where there is a high probability of
finding the electron.finding the electron.• a. s orbital- the simplest has a spherical shapea. s orbital- the simplest has a spherical shape• 1. 1 possible orientation in space1. 1 possible orientation in space• 2. surrounds the nucleus2. surrounds the nucleus• b. P orbital-b. P orbital-• 1) Dumbbell shaped1) Dumbbell shaped• 2) 3 orientations in space ( X.Y,Z)2) 3 orientations in space ( X.Y,Z)• c. d and f orbitals- much more complexc. d and f orbitals- much more complex• 1) 5 possible d orbitals1) 5 possible d orbitals• 2) 7 possible f orbitals2) 7 possible f orbitals• 2. Electrons occupy the lowest energy levels in the atom, 2. Electrons occupy the lowest energy levels in the atom,
and within the levels they occupy orbitals with the lowest amount and within the levels they occupy orbitals with the lowest amount of energy.of energy.
• 2. Electrons occupy the lowest energy levels 2. Electrons occupy the lowest energy levels in the atom, and within the levels they occupy in the atom, and within the levels they occupy orbitals with the lowest amount of energy.orbitals with the lowest amount of energy.
• a. s has lowest then p followed by d and fa. s has lowest then p followed by d and f
• 3. Valence electrons- The outer level of 3. Valence electrons- The outer level of electronselectrons
• a. The combining ability of the atom a. The combining ability of the atom depends on the valencedepends on the valence
• IV TOUR OF THE PERIODIC TABLEIV TOUR OF THE PERIODIC TABLE• A. Organization of the periodic tableA. Organization of the periodic table• 1. Developed by Dmitri Mendeleev 18691. Developed by Dmitri Mendeleev 1869• a. arranged the elements according to repeating a. arranged the elements according to repeating
propertiesproperties• b. He left blank spaces for elements yet to be b. He left blank spaces for elements yet to be
discovered.discovered.• 2. Groups similar elements together2. Groups similar elements together• a. makes it easier to predict propertiesa. makes it easier to predict properties• b. arranged based on the number of protons in b. arranged based on the number of protons in
the nucleusthe nucleus• c. Periodic Law-properties of elements tend to c. Periodic Law-properties of elements tend to
change in a regular pattern when elements are arranged in change in a regular pattern when elements are arranged in order of increasing atomic number or the number of order of increasing atomic number or the number of protons in their atom.protons in their atom.
• B. Using the periodic tableB. Using the periodic table• 1. Periods- horizontal rows1. Periods- horizontal rows• a. increasing number of protonsa. increasing number of protons• b. each period represents the energy b. each period represents the energy
levels of electrons.levels of electrons.• • 2. Groups( family)- the vertical columns2. Groups( family)- the vertical columns• a. tells the number of valance a. tells the number of valance
the chemical properties of the elementthe chemical properties of the element•
• C Ionization- The process of adding or C Ionization- The process of adding or removing electrons from an atom,removing electrons from an atom,
• thus forming a charged atom .thus forming a charged atom .• 1. remove an electron the atom will 1. remove an electron the atom will
have more protons than electrons, and the have more protons than electrons, and the atom is positive( metals)- atom is positive( metals)- CATIONSCATIONS
• 2. add an electron to the atom. The 2. add an electron to the atom. The atom will have more electrons than atom will have more electrons than protons, thus it will be protons, thus it will be negative( nonmetals) negative( nonmetals) ANIONSANIONS
• D. HOW ATOMS DIFFER IN STRUCTURED. HOW ATOMS DIFFER IN STRUCTURE• 1. ATOMIC NUMBER(Z)- This tells the number of 1. ATOMIC NUMBER(Z)- This tells the number of
protons and electrons in an electrically neutral protons and electrons in an electrically neutral atom.atom.
• 2. Mass number- This is the total number of 2. Mass number- This is the total number of protons and neutrons in an atom.protons and neutrons in an atom.
• a. isotope- An atom with the same atomic a. isotope- An atom with the same atomic number, but different atomic massnumber, but different atomic mass
• b. calculating the number of neutrons- The b. calculating the number of neutrons- The mass number- atomic numbermass number- atomic number
• 3. Atomic mass unit- equal to 1/12 3. Atomic mass unit- equal to 1/12 the mass of a carbon-12 atomthe mass of a carbon-12 atom
• 4. Average atomic mass- This is 4. Average atomic mass- This is an umber which represents the an umber which represents the average of the atomic masses average of the atomic masses including every isotope.including every isotope.
PERIODIC TABLE OF THE PERIODIC TABLE OF THE ELEMENTSELEMENTS
• V.Broad classification-V.Broad classification-
• 1. metals characteristics- left side of P.T.1. metals characteristics- left side of P.T.
• a. shinya. shiny
• b. ductile- pulled into wireb. ductile- pulled into wire
• c. malleable- pounded into sheetsc. malleable- pounded into sheets
• d. excellent conductors of heat and d. excellent conductors of heat and electricityelectricity
• e. Donate electrons- become + ione. Donate electrons- become + ion
• 2. Nonmetals characteristics- right side 2. Nonmetals characteristics- right side of P.T.of P.T.
• a. dulla. dull
• b. brittleb. brittle
• c. poor conductorsc. poor conductors
• d. Accept electrons= negative d. Accept electrons= negative ionion
•
• 3. Metalliods- along the zig-zag3. Metalliods- along the zig-zag
• a. properties of metals and a. properties of metals and nonmetalsnonmetals
• b. semiconductorsb. semiconductors
• VI SURVEY OF THE PERIODIC VI SURVEY OF THE PERIODIC TABLETABLE
• A.ALKALI METALS (Group 1)A.ALKALI METALS (Group 1)• 1 soft high reactive metals. 1 soft high reactive metals. • 2.When mixed with water they form a slippery 2.When mixed with water they form a slippery
solution that can remove grease. solution that can remove grease. • 3.Alkali metals are bases, and are highly reactive 3.Alkali metals are bases, and are highly reactive
because they have only one electron in the because they have only one electron in the outermost shell….why?outermost shell….why?
• 4. Alkali metals are good conductors of 4. Alkali metals are good conductors of electricity. Sodium is used in street lamps and fog electricity. Sodium is used in street lamps and fog lights. lights.
• 5. Lithium is used as a medication to treat 5. Lithium is used as a medication to treat depression.depression.
• B.ALKALINE EARTH METALS (Group 2)B.ALKALINE EARTH METALS (Group 2)• 1 are harder, denser, stronger, and have higher 1 are harder, denser, stronger, and have higher
melting points that the group 1 metals.melting points that the group 1 metals.• 2.These metals are less reactive than group 1 2.These metals are less reactive than group 1
because they have 2 electrons in the outer shell.because they have 2 electrons in the outer shell.• 3. In order for them to have a full outer shell 3. In order for them to have a full outer shell
they must loose two electrons. they must loose two electrons. • 4.Magnesium is used in construction because 4.Magnesium is used in construction because
of its strength and lightness. of its strength and lightness. • 5.Calcium is the best know of the alkali earth 5.Calcium is the best know of the alkali earth
metals. metals. •
• C. TRANSITION ELEMENTS (Group 3-12) are C. TRANSITION ELEMENTS (Group 3-12) are all metals. all metals.
• 1.Transition metals are not as reactive as 1.Transition metals are not as reactive as metals in groups 1 & 2. metals in groups 1 & 2.
• 2.They are harder denser and have higher 2.They are harder denser and have higher melting points than groups 1 and 2. melting points than groups 1 and 2.
• 3.Transition elements do not have 3.Transition elements do not have similar electron configurations as do groups similar electron configurations as do groups 1 & 2.1 & 2.
• 4.There are two more periods of 4.There are two more periods of transition elements located at the bottom of transition elements located at the bottom of the periodic table.the periodic table.
• D. Boron family- group 13D. Boron family- group 13
• 1. Boron- used in control rods 1. Boron- used in control rods of nuclear reactors, and detergentsof nuclear reactors, and detergents
• a. 3 valence electronsa. 3 valence electrons
• 2. aluminum- Used as a light 2. aluminum- Used as a light weight metal in industry.weight metal in industry.
•
• E. Carbon familyE. Carbon family• 1. 4 valence electrons1. 4 valence electrons• 2. CARBON2. CARBON• a. Basis of life on this planeta. Basis of life on this planet• b, Bonds with itself and many other b, Bonds with itself and many other
elementselements• 3. Silicon and germanium- the heart of the 3. Silicon and germanium- the heart of the
computer industrycomputer industry• 4. Tin- Acts as a metal - alloys to make 4. Tin- Acts as a metal - alloys to make
useful metalsuseful metals• 5. Lead- Usually the end product of 5. Lead- Usually the end product of
radioactive decayradioactive decay• a. very densea. very dense
• F. NITROGEN FAMILYF. NITROGEN FAMILY• 1. 5 valence electrons1. 5 valence electrons• 2. nitrogen and phosphorus- Used in 2. nitrogen and phosphorus- Used in
fertilizers and explosivesfertilizers and explosives• 3. Arsenic- a poison used in 3. Arsenic- a poison used in
insecticides.insecticides.• 4. Bismuth- Used in automatic 4. Bismuth- Used in automatic
sprinkler systems because it has a low sprinkler systems because it has a low melting pointmelting point
• G. OXYGEN FAMILYG. OXYGEN FAMILY• 1)6 valence electrons- wants 2 to be full, fairly 1)6 valence electrons- wants 2 to be full, fairly
reactivereactive• 2) Oxygen- reactive2) Oxygen- reactive• a. Used in respiration to release ATPa. Used in respiration to release ATP• 3) Sulfur- some in ringed forms3) Sulfur- some in ringed forms• a, Vulcanization of rubber- makes rubber a, Vulcanization of rubber- makes rubber
hardenharden• b. Selinium- poisonous, but necessary in small b. Selinium- poisonous, but necessary in small
• H. HALOGENS- SALT PRODUCERSH. HALOGENS- SALT PRODUCERS• 1. 7 valence electrons... very reactive, only want 1 1. 7 valence electrons... very reactive, only want 1
electronelectron• 2. fluorine- very reactive and poisonous2. fluorine- very reactive and poisonous• a. Used to etch glass- HF acida. Used to etch glass- HF acid• 3. Chlorine- Very poisonous3. Chlorine- Very poisonous• a. used in bleaches and detergents- sodium a. used in bleaches and detergents- sodium
hyperchloridehyperchloride• 4. Bromine- purple liquid at room temperature4. Bromine- purple liquid at room temperature• 5. iodine- Gray crystals5. iodine- Gray crystals• a. sublimes when heateda. sublimes when heated• b. necessary for the proper functioning of the b. necessary for the proper functioning of the
• I. NOBLE GASES- VERY BORINGI. NOBLE GASES- VERY BORING• A) 8 electrons in the valence level, so all A) 8 electrons in the valence level, so all
levels are full.levels are full.• B) He is lighter than air so used in airshipsB) He is lighter than air so used in airships• a. helium comes from the Greek a. helium comes from the Greek
workwork helios helios which means sun which means sun• 1. discovered by studying the spectrum 1. discovered by studying the spectrum
of sunlightof sunlight• 2) the rest of them are used in lighted 2) the rest of them are used in lighted
signs or as gases to extend the life of light bulbssigns or as gases to extend the life of light bulbs•
• VII. USING MOLES TO COUNT VII. USING MOLES TO COUNT ATOMSATOMS
• A. ITS LIKE A PACKAGING TERMA. ITS LIKE A PACKAGING TERM
• B. CHEMIST DEAL WITH A LARGE B. CHEMIST DEAL WITH A LARGE NUMBER OF SMALL PARTICLES.NUMBER OF SMALL PARTICLES.
• 1. Mole-The SI unit which 1. Mole-The SI unit which describes the amount of a substancedescribes the amount of a substance
• a. 1 Mole of anything is a. 1 Mole of anything is 6.022x106.022x102323 of anything of anything
• 1) 6.022x101) 6.022x102323 is Avogado’s is Avogado’s constantconstant
• 2. Molar mass(FWIG)- The mass of 1 mole 2. Molar mass(FWIG)- The mass of 1 mole of any substance, or the mass of 6.02x10of any substance, or the mass of 6.02x102323 of anythingof anything
• a. The average atomic mass is the a. The average atomic mass is the weight of 1 mole of the substanceweight of 1 mole of the substance
• 1. 16g of oxygen = 1 mole1. 16g of oxygen = 1 mole• 2. 18g of H2. 18g of H22 O =1Mole O =1Mole• 3.molar mass of NaCl is?3.molar mass of NaCl is?• b. The molecular weight of a b. The molecular weight of a
compound also equals 1 molecompound also equals 1 mole
• C Using conversion factors for calculating molesC Using conversion factors for calculating moles• 1. Must make sure all the units cancel away, and end up with 1. Must make sure all the units cancel away, and end up with
the desired units.the desired units.• PRACTICEPRACTICE• 1. HOW MANY MOLES OF WATER ARE IN 72 g OF WATER1. HOW MANY MOLES OF WATER ARE IN 72 g OF WATER• 72gx 1m/18g=4M72gx 1m/18g=4M• 2. HOW MANY PARTICLES ARE IN 72 g OF WATER2. HOW MANY PARTICLES ARE IN 72 g OF WATER• 4Mx 6.02x104Mx 6.02x102323 particles/1mole= 24.08x10 particles/1mole= 24.08x102323 particles• 3. HOW MANY MOLES ARE IN 174g OF NaCl3. HOW MANY MOLES ARE IN 174g OF NaCl• 174gx 1m/58g=3M174gx 1m/58g=3M• 4.THE NUMBER OF PARTICLES IN NaCl4.THE NUMBER OF PARTICLES IN NaCl• 4M x 6.02x104M x 6.02x102323 particles particles• •
• 30g of HCl=______atom30g of HCl=______atom• 30gx 1m/36g x 6.02x1030gx 1m/36g x 6.02x102323atoms/1matoms/1m• 98g of H98g of H22 SO SO44=_______atoms=_______atoms• 98gx 1m/98g x 6.02x1098gx 1m/98g x 6.02x102323 atoms/m atoms/m• 300 g of Ba300 g of Ba33 (PO (PO44))22=______atoms=______atoms• 300g x 1m/601g x 6.02 x10300g x 1m/601g x 6.02 x102323 /m /m• 6M of NaCl=_______________atoms6M of NaCl=_______________atoms• 6M x 6.02 x106M x 6.02 x102323 atoms/m atoms/m• .9M of H.9M of H22 O=___________atoms O=___________atoms
