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8/11/2019 Atomic Structure power points
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http://lawrencekok.blogspot.com
Prepared byLawrence Kok
Tuto r ial on A tom ic Structu re, Part ic le
Phys ics and Relat ive A tom ic Mass.
http://lawrencekok.blogspot.com/http://lawrencekok.blogspot.com/8/11/2019 Atomic Structure power points
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Atomic Structure
Atomic Size radiusOrder of magnitude (10-10 10-12)mRadius Li atom (1.5 x 10-10)mRadius nucleus (1 x 10-14)m
Radius Li
atom
Radius Nucleus
Li atom
Nucleon made up of (protons + neutrons)Protons made up of 2 up quarks + 1 down quark
Neutron made up of 2 down quarks + 1 up quark
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Atomic Structure
Atomic Size radiusOrder of magnitude (10-10 10-12)mRadius Li atom (1.5 x 10-10)mRadius nucleus (1 x 10-14)m
1nm 1 x 10-9 m1pm 1 x 10-12 m1A - 1 x 10-10 m
Radius Li
atom
Radius Nucleus
Li atomElementary particles making upnucleon (protons + neutrons)
Nucleon made up of (protons + neutrons)Protons made up of 2 up quarks + 1 down quark
Neutron made up of 2 down quarks + 1 up quark
Unit conversion
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Atomic Structure
Atomic Size radiusOrder of magnitude (10-10 10-12)mRadius Li atom (1.5 x 10-10)mRadius nucleus (1 x 10-14)m
Scale/size of matter from smallest to largest
Excellent Flash on scale of universe Excellent Flash on biological cells Video on scale of universe
1nm 1 x 10-9 m1pm 1 x 10-12 m1A - 1 x 10-10 m
Radius Li
atom
Radius Nucleus
Li atomElementary particles making upnucleon (protons + neutrons)
Nucleon made up of (protons + neutrons)Protons made up of 2 up quarks + 1 down quark
Neutron made up of 2 down quarks + 1 up quark
Unit conversion
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Atomic Structure
Atomic Size radiusOrder of magnitude (10-10 10-12)mRadius Li atom (1.5 x 10-10)mRadius nucleus (1 x 10-14)m
1nm 1 x 10-9 m1pm 1 x 10-12 m1A - 1 x 10-10 m
Radius Li
atom
Radius Nucleus
Li atomElementary particles making upnucleon (protons + neutrons)
Nucleon made up of (protons + neutrons)Protons made up of 2 up quarks + 1 down quark
Neutron made up of 2 down quarks + 1 up quark
Unit conversion
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Atomic Structure
Atomic Size radiusOrder of magnitude (10-10 10-12)mRadius Li atom (1.5 x 10-10)mRadius nucleus (1 x 10-14)m
1nm 1 x 10-9 m1pm 1 x 10-12 m1A - 1 x 10-10 m
Radius Li
atom
Radius Nucleus
Li atomElementary particles making upnucleon (protons + neutrons)
Nucleon made up of (protons + neutrons)Protons made up of 2 up quarks + 1 down quark
Neutron made up of 2 down quarks + 1 up quark
Unit conversion
Structure within atom
Recent discovery particles with help of Large HadronCollider
Video on new particles physics
http://astronomyonline.org/ViewImage.asp?Cate=Home&SubCate=MP01&SubCate2=&Img=%2FScience%2FImages%2FAtomicStructure.jpg&C
pt
http://astronomyonline.org/ViewImage.asp?Cate=Home&SubCate=MP01&SubCate2=&Img=/Science/Images/AtomicStructure.jpg&Cpthttp://astronomyonline.org/ViewImage.asp?Cate=Home&SubCate=MP01&SubCate2=&Img=/Science/Images/AtomicStructure.jpg&Cpthttp://justintymewrites.wordpress.com/2012/06/20/the-standard-model-in-laymans-terms2/http://justintymewrites.wordpress.com/2012/06/20/the-standard-model-in-laymans-terms2/http://justintymewrites.wordpress.com/2012/06/20/the-standard-model-in-laymans-terms2/http://justintymewrites.wordpress.com/2012/06/20/the-standard-model-in-laymans-terms2/http://justintymewrites.wordpress.com/2012/06/20/the-standard-model-in-laymans-terms2/http://justintymewrites.wordpress.com/2012/06/20/the-standard-model-in-laymans-terms2/http://justintymewrites.wordpress.com/2012/06/20/the-standard-model-in-laymans-terms2/http://justintymewrites.wordpress.com/2012/06/20/the-standard-model-in-laymans-terms2/http://justintymewrites.wordpress.com/2012/06/20/the-standard-model-in-laymans-terms2/http://justintymewrites.wordpress.com/2012/06/20/the-standard-model-in-laymans-terms2/http://justintymewrites.wordpress.com/2012/06/20/the-standard-model-in-laymans-terms2/http://astronomyonline.org/ViewImage.asp?Cate=Home&SubCate=MP01&SubCate2=&Img=/Science/Images/AtomicStructure.jpg&Cpthttp://astronomyonline.org/ViewImage.asp?Cate=Home&SubCate=MP01&SubCate2=&Img=/Science/Images/AtomicStructure.jpg&Cpt8/11/2019 Atomic Structure power points
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Discovery timeline Democritus to Quantum model
Video on timeline discovery
Discovery of elementary particles
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Discovery timeline Democritus to Quantum model
Video on timeline discovery
Discovery of elementary particles Elementary particles
Structure within atom
Video on new particles physics
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Discovery timeline Democritus to Quantum model
Video on timeline discovery
Discovery of elementary particles Elementary particles
Structure within atom
Video on new particles physics
Recent discovery particlesfrom Large Hadron Collider
Higgs boson leftover excitation of particles of Higgs f ield
Discovery of Higgs boson and Higgs field
Particles interact with Higgs field to produce mass
Video on Higgs field part 1
Video on Higgs field part 2
Higgs Boson Discovery Wins Nobel Prize for Physics
Video on NOBEL PRIZE 2013 !!!!!!
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Elementary particlesStructure within atom
Recent discovery particlesfrom Large Hadron Collider
Discovery of Higgs boson and Higgs field
Particles interact with Higgs field to produce mass
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Elementary particlesStructure within atom
Recent discovery particlesfrom Large Hadron Collider
Discovery of Higgs boson and Higgs field
Particles interact with Higgs field to produce mass
Video on Higgs field
Mass (proton + neutron)- due to interaction betweenup quarks/down quarks with gluons (energy fluatutions)
Proton -2 up quarks 1 down quark
Neutron -1 up quark
2 down quarks
What is Higgs Boson ?What is Higgs Field ?
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Elementary particlesStructure within atom
Recent discovery particlesfrom Large Hadron Collider
Higgs boson leftover excitation of particles of Higgs field
Discovery of Higgs boson and Higgs field
Particles interact with Higgs field to produce mass
Video on Higgs field
Mass (proton + neutron)- due to interaction betweenup quarks/down quarks with gluons (energy fluatutions)
Proton -2 up quarks 1 down quark
Neutron -1 up quark
2 down quarks
What is Higgs Boson ?What is Higgs Field ?
Excellent videos Particles interact with Higgs field to create MASS
Video (Ted Talk) Video (Minute physics)Video (RI)Video (Veratasium)
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Nuclear reaction vs Chemical reaction
Nuclear reactionInvolve protons/neutrons in nucleusDecomposition of nucleus into smaller nuclei Energy released greaterConservation of charge / atomic mass number
Chemical reactionInvolve outer most electronsTransfer/sharing/loss of electronsEnergy released lessConservation of mass and charge
2Na + CI22NaCI
Nuclear equation- decay of nucleus Chemical equationvalence electrons
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Nuclear reaction vs Chemical reaction
Nuclear reactionInvolve protons/neutrons in nucleusDecomposition of nucleus into smaller nuclei Energy released greaterConservation of charge / atomic mass number
Chemical reactionInvolve outer most electronsTransfer/sharing/loss of electronsEnergy released lessConservation of mass and charge
2Na + CI22NaCI
http://ths.talawanda.net/~BrambleN/classroom/Chemistry/Notes/Section%206A%20and%206B/RadioactiveDecay.htm
http://www.classhelp.info/Biology/AUnit3Biochemistry.htm
Typeradiation
Natureradiation
Symbol Penetration(mass,m/charge,e
)
Ionisingpower
(removing electron)
Alpha Heliumnucleus
Low ratio(high m/e)
High
Beta High energyelectron
Moderate Moderate
Gamma High frequencyelectromagnetic
radiation
High ratio(small m/e)
Low
Type of radiation
Nuclear equation- decay of nucleus Chemical equationvalence electrons
Transfer electrons
Sharing electrons
http://ths.talawanda.net/~BrambleN/classroom/Chemistry/Notes/Section%206A%20and%206B/RadioactiveDecay.htmhttp://www.classhelp.info/Biology/AUnit3Biochemistry.htmhttp://www.classhelp.info/Biology/AUnit3Biochemistry.htmhttp://ths.talawanda.net/~BrambleN/classroom/Chemistry/Notes/Section%206A%20and%206B/RadioactiveDecay.htm8/11/2019 Atomic Structure power points
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Nuclear reaction
Alpha Decay Beta Decay
Gamma Decay
Unstable nucleus of atom Decay by emitting ionizing particles
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Nuclear reaction
Alpha DecayLosing an alpha particle helium nucleusDaughter nuclei lower in proton numberMass of 4 (2 proton + 2 neutron)+2 charged (only 2 protons) = +2Decay of uranium, thorium, actinium
Beta DecayLosing beta particle Electron/positronDaughter nuclei higher in proton numberNegative charge (-1)Decay neutron proton + electron
Alpha Decay Beta Decay
Gamma Decay
Gamma decayLosing a particle - electromagnetic radiation ofhigh frequencyDaughter nuclei no change in atomic mass
Unstable nucleus of atom Decay by emitting ionizing particles
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Nuclear reaction
http://ths.talawanda.net/~BrambleN/classroom/Chemistry/Notes/Section%206A%20and%206B/RadioactiveDecay.htm
http://molaire1.perso.sfr.fr/e_radioactiv.html
Alpha DecayLosing an alpha particle helium nucleusDaughter nuclei lower in proton numberMass of 4 (2 proton + 2 neutron)+2 charged (only 2 protons) = +2Decay of uranium, thorium, actinium
Beta DecayLosing beta particle Electron/positronDaughter nuclei higher in proton numberNegative charge (-1)Decay neutron proton + electron
Alpha Decay Beta Decay
Gamma Decay
Gamma decayLosing a particle - electromagnetic radiation ofhigh frequencyDaughter nuclei no change in atomic mass
Unstable nucleus of atom Decay by emitting ionizing particles
+
http://ths.talawanda.net/~BrambleN/classroom/Chemistry/Notes/Section%206A%20and%206B/RadioactiveDecay.htmhttp://molaire1.perso.sfr.fr/e_radioactiv.htmlhttp://molaire1.perso.sfr.fr/e_radioactiv.htmlhttp://ths.talawanda.net/~BrambleN/classroom/Chemistry/Notes/Section%206A%20and%206B/RadioactiveDecay.htm8/11/2019 Atomic Structure power points
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Difference Between Alpha, Beta and Gamma Radiation
Alpha DecayLose alpha particle helium nucleusMass He- 4 (2 proton + 2 neutron)+2 charged (2 proton + 2 neutron + 0 e)Daughter nuclei lower in proton number
Beta DecayLose beta particle Electron/beta Negative charge (-1)-1 charged ( or electron)Daughter nuclei higher in proton number
Gamma decayLose a particle electromagnetic radiation ofhigh frequencyDaughter nuclei no change in atomic mass
Nucleus > 84 protonsUnstable, radioactive decayDecay depends on ratio neutron/proton
Mass number always Conserved/Same
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Difference Between Alpha, Beta and Gamma Radiation
Alpha DecayLose alpha particle helium nucleusMass He- 4 (2 proton + 2 neutron)+2 charged (2 proton + 2 neutron + 0 e)Daughter nuclei lower in proton number
Beta DecayLose beta particle Electron/beta Negative charge (-1)-1 charged ( or electron)Daughter nuclei higher in proton number
Gamma decayLose a particle electromagnetic radiation ofhigh frequencyDaughter nuclei no change in atomic mass
Nucleus > 84 protonsUnstable, radioactive decayDecay depends on ratio neutron/proton
Decay depend on ratio neutron/protonNeutron/proton ratio LOW Proton richDecay to reduce proton-Alpha decay, (proton number )
Mass number always Conserved/Same
Decay depend on ratio neutron/protonNeutron/proton ratio HIGH Neutron richDecay to reduce neutron-Beta decay ( Neutron Proton + electron)-Ratio decrease
Decay depend on ratio neutron/protonNeutron/proton ratio HIGH /LOW-Gamma decay , is associated along with Alpha and Beta
Video on decay Video on decay Video on decay
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Isotopes
Stable IsotopesUnstable Isotopes
Unstable Isotopes emits radiation
RADIOISOTOPES
RadioisotopesHalf-life timetaken for conc/amt isotope to fall to half of its original value.Half life decay always constant
Emit radiation form unstableisotope
I
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Radioactiveisotopes
Half-life
Uranium 238 4.5 x 109
Carbon-14 5.7 x 103
Radium-226 1.6 x 103
Strontium-90 28 years
Iodine-131 8.1 days
Bismuth-214 19.7minutes
Polonium-214 1.5 x 10-4
Isotopes
Stable IsotopesUnstable Isotopes
Unstable Isotopes emits radiation
RADIOISOTOPES
RadioisotopesHalf-life timetaken for conc/amt isotope to fall to half of its original value.Half life decay always constant
Shorter half-lifeMore unstable, decay fast
Long half-lifeMore stable, decay slowly
www.sciencelearn.org.nz
Emit radiation form unstableisotope
Half-life
I
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Radioactiveisotopes
Half-life
Uranium 238 4.5 x 109
Carbon-14 5.7 x 103
Radium-226 1.6 x 103
Strontium-90 28 years
Iodine-131 8.1 days
Bismuth-214 19.7minutes
Polonium-214 1.5 x 10-4
Isotopes
Stable IsotopesUnstable Isotopes
Unstable Isotopes emits radiation
RADIOISOTOPES
Simulation isotope 12C, 13C, 14C
RadioisotopesHalf-life timetaken for conc/amt isotope to fall to half of its original value.Half life decay always constant
Shorter half-lifeMore unstable, decay fast
Long half-lifeMore stable, decay slowly
www.sciencelearn.org.nz
Emit radiation form unstableisotope
Simulation isotope 1H, 2H, 3H
Video on Half life
Simulation half life C-14/uranuim
Half-life
C b I t
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Carbon 3 Isotopes Radiocarbon/carbon dating
Carbon -12 Carbon -14Carbon -13
Abundance 99% (Stable) Abundance 1% (Stable) Abundance trace amt(Unstable , radioactive)
Carbon 3 Isotopes
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Carbon 3 Isotopes Radiocarbon/carbon dating
Half life C-14 = 5730 yearsBeta (/electron ) decay
Carbon -12 Carbon -14Carbon -13
Abundance 99% (Stable) Abundance 1% (Stable) Abundance trace amt(Unstable , radioactive)
How is form?C-14 produce in stratosphere when.. neutron hit a nitrogen atom to form C-14C-14 to N-14 by converting neutron proton (proton stay in nucleus), electron emit as radiation
emit as ray.
(proton in nucleus increase proton number)
emit as ray.
Ratio C14/C12- constantif aliveTAKEin C14 (C12 constant)
Ratio C14/C12- dropif dead- NOTtaking C14. (C12 constant)
How it is form?
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R di b / b d i
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Radiocarbon/carbon dating
Half life C-14 = 5730 yearsBeta (/electron ) decay
Carbon -14
Abundance trace amt(Unstable , radioactive)
How is form?C-14 produce in stratosphere when.. neutron hit a nitrogen atom to form C-14C-14 to N-14 by converting neutron proton (proton stay in nucleus), electron emit as radiation
emit as ray.
(proton in nucleus increase protonnumber)
emit as ray.
Ratio C14/C12- constantif aliveTAKEin C14 (C12 constant)Ratio C14/C12- dropif dead- NOTtaking C14. (C12 constant)
R di b / b d ti
H R di b d ti k ?
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Radiocarbon/carbon dating
Half life C-14 = 5730 yearsBeta (/electron ) decay
Carbon -14
Abundance trace amt(Unstable , radioactive)
How is form?C-14 produce in stratosphere when.. neutron hit a nitrogen atom to form C-14C-14 to N-14 by converting neutron proton (proton stay in nucleus), electron emit as radiation emit as ray.
(proton in nucleus increase protonnumber)
emit as ray.
Ratio C14/C12- constantif aliveTAKEin C14 (C12 constant)Ratio C14/C12- dropif dead- NOTtaking C14. (C12 constant)
Simulation C-14 (Half life)At 100% (Starting)
Simulation C-14 (Half life)At 50% (Starting)
Click toview simulation
How Radiocarbon dating works?
R di b / b d ti
H R di b d ti k ?
http://phet.colorado.edu/en/simulation/radioactive-dating-gamehttp://phet.colorado.edu/en/simulation/radioactive-dating-game8/11/2019 Atomic Structure power points
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Radiocarbon/carbon dating
Half life C-14 = 5730 yearsBeta (/electron ) decay
Carbon -14
Abundance trace amt(Unstable , radioactive)
How is form?C-14 produce in stratosphere when.. neutron hit a nitrogen atom to form C-14C-14 to N-14 by converting neutron proton (proton stay in nucleus), electron emit as radiation emit as ray.
(proton in nucleus increase protonnumber)
emit as ray.
Ratio C14/C12- constantif aliveTAKEin C14 (C12 constant)Ratio C14/C12- dropif dead- NOTtaking C14. (C12 constant)
Video on C-14 Carbon Dating Video on C-14 Carbon Dating/Fossil Video on C-14 Half life Carbon Dating
Simulation C-14 (Half life)At 100% (Starting)
Simulation C-14 (Half life)At 50% (Starting)
Video on Radiocarbon dating
Click toview simulation
How Radiocarbon dating works?
Uses of radioactive isotopes
http://phet.colorado.edu/en/simulation/radioactive-dating-gamehttp://phet.colorado.edu/en/simulation/radioactive-dating-game8/11/2019 Atomic Structure power points
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Radiocarbon/carbon dating
Carbon -14
Uses of radioactive isotopes
Radiotherapy/cancer/tumour Tracers/studying metabolic pathways
Cobalt-60Iodine-131
Uses of radioactive isotopes
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Radiocarbon/carbon dating
Half life C-14 = 5730 years
Carbon -14
Beta (/electron) decay
How Radiocarbon dating works?
Uses of radioactive isotopes
Radiotherapy/cancer/tumour Tracers/studying metabolic pathways
Cobalt-60
Half life Co-60 = 5.27 years Half life I-131 = 8 days
How Gamma rays works?How Radio tracer works?
Iodine-131
Sterilization killing bacteria/germRadiotherapy kill tumor cellsHigh energy electromagnetic ray
Gamma + decay
Carbon datingAge of fossil remains
Radio tracerTrace the pathway in bodyBeta (90%) and (10%) decay
Gamma + decay
Uses of radioactive isotopes
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Radiocarbon/carbon dating
Half life C-14 = 5730 years
Carbon -14
Beta (/electron) decay
Video on C-14 Carbon Dating
Video on Radiocarbon dating
How Radiocarbon dating works?
Uses of radioactive isotopes
Radiotherapy/cancer/tumour Tracers/studying metabolic pathways
Cobalt-60
Half life Co-60 = 5.27 years Half life I-131 = 8 days
How Gamma rays works?How Radio tracer works?
Iodine-131
Sterilization killing bacteria/germRadiotherapy kill tumor cellsHigh energy electromagnetic ray
Video on Radio tracerVideo on Radiotherapy
Gamma + decay
Carbon datingAge of fossil remains
Radio tracerTrace the pathway in bodyBeta (90%) and (10%) decay
Gamma + decay
No isotopes are present
Atomic /Mass number
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6 protons + 6 neutrons
8 protons
Proton number = proton
Mass number = proton + neutron
Z
A
6 protons
8 protons + 8 neutrons
No isotopes are present
Atomic /Mass number
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6 protons + 6 neutrons
8 protons
Proton number = proton
Mass number = proton + neutron
Z
A
6 protons
Atomic Weight With isotopes present
8 protons + 8 neutrons
Proton number = proton Z
Mean relative mass (atomic weight) A
Video on weighted average
Relative Atomic Mass N i t t
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Relative Atomic Mass, (Ar) of an element:Number of times one atom of the element is heavier than one twelfth of the mass of a carbon-12Relative atomic mass = Mass of one atom of element 1/12 x mass of one carbon-12Relative atomic mass for sulphur = 32 (one sulphur atom is 32 x heavier than 1/12 of mass of one (C12)
Relative Atomic Mass
Relative Atomic Mass is used :Impossible to weigh an atom in gramsCompare how heavy one atom is to carbon (standard)One sulphur atom 32x heavier than 1/12 carbon -12Carbon -12 used as standard
No isotopes are present
Mass number = proton + neutron
Proton number = protonZ
AMass number Average atomic mass (atomic mass unit)
Relative Atomic Mass No isotopes are present
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Relative Atomic Mass, (Ar) of an element:Number of times one atom of the element is heavier than one twelfth of the mass of a carbon-12Relative atomic mass = Mass of one atom of element 1/12 x mass of one carbon-12Relative atomic mass for sulphur = 32 (one sulphur atom is 32 x heavier than 1/12 of mass of one (C12)
http://www.tutorvista.com/content/science/science-i/atoms-molecules/atom.php
Relative Atomic Mass
Carbon-12 as standard1/12 of C12 = 1 unit
Sulphur 32x heavier
1/12 x = 1 unit
32 unit
6 protons + 6 neutrons
16 protons + 16 neutrons
Relative Atomic Mass is used :Impossible to weigh an atom in gramsCompare how heavy one atom is to carbon (standard)One sulphur atom 32x heavier than 1/12 carbon -12Carbon -12 used as standard
12
6
32
16
No isotopes are present
Mass number = proton + neutron
Proton number = protonZ
A
Assuming No isotopes present!
Mass number Average atomic mass (atomic mass unit)
Relative Molecular Mass No isotopes are present
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Relative Molecular Mass, (Mr):Number of times one molecule is heavier than one twelfth of the mass of a carbon-12 Relative molecular mass = Mass of one molecule 1/12 x mass of one carbon-12Relative molecular mass for H2O= 18 (one H2O is 18 x heavier than 1/12 of mass of one(C12)
Relative Molecular Mass is used :Impossible to weigh an molecules in gramsCompare one molecule to carbon (standard)One H2O is 18 x heavier than 1/12 carbon -12Carbon -12 is used as standard
Relative Molecular Mass No isotopes are present
Proton number = proton
Mass number = proton + neutron
Z
AMass number Average atomic weight (atomic mass unit)
Relative Molecular Mass No isotopes are present
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Relative Molecular Mass, (Mr):Number of times one molecule is heavier than one twelfth of the mass of a carbon-12 Relative molecular mass = Mass of one molecule 1/12 x mass of one carbon-12Relative molecular mass for H2O= 18 (one H2O is 18 x heavier than 1/12 of mass of one(C12)
http://www.tutorvista.com/content/science/science-i/atoms-molecules/atom.php
Relative Molecular Mass is used :Impossible to weigh an molecules in gramsCompare one molecule to carbon (standard)One H2O is 18 x heavier than 1/12 carbon -12Carbon -12 is used as standard
Relative Molecular Mass
Carbon-12 as standard1/12 of C12 = 1 unit
H2O 18x heavier
1/12 x = 1 unit
16 unit
2 unit
18 unit
+
6 protons + 6 neutrons
8 protons + 8 neutrons
No isotopes are present
Proton number = proton
Mass number = proton + neutron
Z
A
Assuming No isotopes present!
Mass number Average atomic weight (atomic mass unit)
2 protons
Relative Isotopic Mass Presence of isotopes
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Relative Isotopic Mass
Isotopes Atoms of same element withDifferent number of neutronsSame number of protons and electronsDue to presence of isotopes, when calculating RAM,
weighted average/mean of all isotopes present is used.
Mass number = proton + neutron
Proton number = proton Z = 29 protons
A= 29 protons + 35 neutrons = 64
Z
Presence of isotopes
A
Z
A
Relative Isotopic Mass Presence of isotopes
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Relative Isotopic Mass
Isotopes Atoms of same element withDifferent number of neutronsSame number of protons and electronsDue to presence of isotopes, when calculating RAM,
weighted average/mean of all isotopes present is used.
X - No isotopes
RAM/Ar X = 11Mass of 1 atom X Mass of 1/12 of 12CMass of 1 atom X relative to
1/12 mass of 1 atom 12C Relative Abundance 75% 25%
Mass number = proton + neutron
Proton number = proton Z = 29 protons
A= 29 protons + 35 neutrons = 64
Isotopes Y - TWOisotopes
RAM/Ar Y = 10.5AverageMass of 1 atom Y Mass of 1/12 of 12CAveragemass of 1 atom Y relative to
1/12 mass of 1 atom 12C
CI - TWOisotopes
Relative Abundance 50% 50%
Z
Presence of isotopes
A
Z
A
11
3
17
35
17
37
3 3
10 11
Relative Isotopic Mass Presence of isotopes
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Relative Isotopic Mass
Isotopes Atoms of same element withDifferent number of neutronsSame number of protons and electronsDue to presence of isotopes, when calculating RAM,
weighted average/mean of all isotopes present is used.
X - No isotopes
RAM/Ar X = 11Mass of 1 atom X Mass of 1/12 of 12CMass of 1 atom X relative to
1/12 mass of 1 atom 12C Relative Abundance 75% 25%
Mass number = proton + neutron
Proton number = proton Z = 29 protons
A= 29 protons + 35 neutrons = 64
Isotopes Y - TWOisotopes
RAM/Ar Y = 10.5AverageMass of 1 atom Y Mass of 1/12 of 12CAveragemass of 1 atom Y relative to
1/12 mass of 1 atom 12C
RAM /Ar, CI = 35.5Weighted average mass of 2 isotopes present= (mass 35CI x % Abundance) + (mass 37CI x %
Abundance)= (35 x 75/100) + (37 x 25/100)= 35.5
CI - TWOisotopes
Relative Abundance 50% 50%
Z
Presence of isotopes
A
Z
A
11
3
17
35
17
37
3 3
10 11
Relative Atomic Mass Isotopes are present
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p p
Weighted average mass- due to presence of isotopes
RAM = 12.01
Relative Abundance 98.9% 1.07%
13
Why RAM is not a whole number?
12
Relative Atomic Mass Isotopes are present
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p p
Weighted average mass- due to presence of isotopes
Relative Isotopic Mass, (Ar) of an element:Relative isotopic mass = Average mass of one atom of element 1/12 x mass of one carbon-12Relative isotopic mass, carbon = 12.01
RAM = 12.01
Relative Abundance 98.9% 1.07%
13
Why RAM is not a whole number?
RAM, C := (Mass 12C x % Abundance) + (Mass 13C x % Abundance)= (12 x 98.9/100) + (13 x 1.07/100) = 12.01
12
Relative Atomic Mass Isotopes are present
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http://www.tutorvista.com/content/science/science-i/atoms-molecules/atom.php
Weighted average mass- due to presence of isotopes
Relative Isotopic Mass, (Ar) of an element:Relative isotopic mass = Average mass of one atom of element 1/12 x mass of one carbon-12Relative isotopic mass, carbon = 12.01
Video on Isotopes
RAM = 12.01
Relative Abundance 98.9% 1.07%
13
Why RAM is not a whole number?
RAM, C := (Mass 12C x % Abundance) + (Mass 13C x % Abundance)= (12 x 98.9/100) + (13 x 1.07/100) = 12.01
Video on weighted average Weighted average calculation
Video on Isotopes
RAM calculation
12
Relative Atomic Mass
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Mg - 3 Isotopes
24 Mg (100/127.2) x 100% -78.6%25 Mg (12.8/127.2) x 100% -10.0%26 Mg (14.4/127.2) x 100% -11.3%
RAM for Mg :
= (Mass 24Mg x % Abundance) + (Mass 25Mg x % Abundance) + (Mass 26Mg x % Abundance)= (24 x 78.6/100) + (25 x 10.0/100) + (26 x 11.3/100) = 24.30
Relative Abundance % Abundance
Convert relative abundance to % abundance
Relative Atomic Mass
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Mg - 3 Isotopes
24 Mg (100/127.2) x 100% -78.6%25 Mg (12.8/127.2) x 100% -10.0%26 Mg (14.4/127.2) x 100% -11.3%
RAM for Mg :
= (Mass 24Mg x % Abundance) + (Mass 25Mg x % Abundance) + (Mass 26Mg x % Abundance)= (24 x 78.6/100) + (25 x 10.0/100) + (26 x 11.3/100) = 24.30
Relative Abundance % Abundance
Pb - 4 Isotopes
204Pb (0.2/10) x 100% -2%206Pb (2.4/10) x 100% -24%207Pb (2.2/10) x 100% -22%208Pb (5.2/10) x 100% -52%RAM for Pb :
= (Mass 204Pb x % Abundance) + (Mass 206Pb x % Abundance) + (Mass 207Pb x % Abundance) + (Mass 208Pb x % Abundance)= (204 x 2/100) + (206 x 24/100) + (207 x 22/100) + (208 x 52/100) = 207.20
Convert relative abundance to % abundance
Convert relative abundance to % abundance
Relative Abundance % Abundance
Additional Resources
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Simulation C-14 dating (Half life) Simulation U-238 dating (Half life)
Video on isotopes using mass spec Video on Particle Physics (Higgs Field)
Simulation on atomic model
Periodic Table from webelement
Simulation isotope 1H, 2H, 3H
and 12C, 13C, 14C
Excellent Video on scale of universe
Video on new particles physics
Excellent Video Higgs Field (Ted Talk)
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Acknowledgements
Thanks to source of pictures and video used in this presentationhttp://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/nucnot.html
http://www.m2c3.com/chemistry/VLI/M3_Topic2/M3_Topic2_print.htmlhttp://www.universityneurosurgery.com/index.php?src
http://www.medwow.com/med/cobalt-linear-accelerator/radon/tr-cobalt-60/42865.model-spec
http://endocrinesurgery.ucla.edu/patient_education_adm_tst_radioactive_iodine_uptake_test.html
Thanks to Creative Commons for excellent contribution on licenseshttp://creativecommons.org/licenses/
Prepared by Lawrenc e Kok
Check out more v ideo tutor ials f rom my si te and hop e you enjoy th is tutor ia lhttp://lawrencekok.blogspot.com