ATOMIC #’S AND N5 ISOTOPES - My Chemistry Class
Target: I can describeadvancements in the modelof the atom, and can countsubatomic particlesATOMIC #’S ANDISOTOPESN5
DALTON’S ATOMIC THEORY(1808)John Dalton1)All matter composedof extremely smallparticles called atoms
DALTON’S ATOMIC THEORY(1808)2) Atoms of a givenJohn Daltonelement are identicalin size, mass, andother properties
DALTON’S ATOMIC THEORY(1808)John Dalton3) Atoms of differentelements differ insize, mass, and otherproperties
DALTON’S ATOMIC THEORY(1808)John Dalton4) Atoms cannot besubdivided, created,or destroyed
DALTON’S ATOMIC THEORY(1808)John Dalton5) Atoms of differentelements combine insimple wholenumber ratios toform chemicalcompounds
DALTON’S ATOMIC THEORY(1808)John Dalton6) In chemical reactions,atoms are combined,separated, orrearranged
DALTON’S BILLIARD BALLMODELJohn Dalton
MODERN ATOMIC THEORY –WHAT WAS WRONG WITHDALTON’S THEORY?Atoms have anAVERAGE MASS!Atoms cannot bedivided, createdor destroyedduring NORMALchemical reactionsIt is an AVERAGEbecause of ISOTOPES!BUT they CAN dothose things duringNUCLEAR reactions!
DISCOVERY OF THE ELECTRONIn 1897, J.J. Thomson used a cathode ray tube todeduce the presence of a negatively chargedparticle.Cathode ray tubes pass electricity through agas that is contained at a very low pressure.https://www.youtube.com/watch?v O9Goyscbazk
CONCLUSIONS FROM THESTUDY OF THE ELECTRONCathode rays haveidentical propertiesregardless of element usedAtoms are neutralElectrons have verylittle mass comparedto the atom’s massAll elements must containidentically chargedelectrons.Must be positive particlesbalancing the negativecharge of electronsAtoms must contain otherheavier particles thataccount for most of themass
THOMSON’S ATOMIC MODELThomson believed that the electronswere like plums embedded in apositively charged “pudding,” thus itwas called the “plum pudding” model.We don’t usually eat plum pudding inthis country, so I like to call it thechocolate chip cookie model.
RUTHERFORD’S GOLD FOIL EXPERIMENT Alpha ( ) particles are helium nuclei Particles were fired at a thin sheet of gold foil Particle hits on the detecting screen (film) are recorded
https://www.youtube.com/watch?v XBqHkraf8iE
RUTHERFORD’S FINDINGS1) Most of the particles passed right through2) A few particles were deflected3) A FEW were greatly deflectedCONCLUSIONS: The nucleus is small The atom is mostlyempty space The nucleus is dense The nucleus ispositively charged
ATOMIC PARTICLESParticle Charge Mass #LocationElectron-10Electron cloudProton 11NucleusNeutron01Nucleus
ATOMIC NUMBERSWe know: Nucleus has protons (p ), neutrons (n0 ), andelectrons(e- ) are on the outside of nucleusBut how many of each?Atomic Mass Number(round to the nearest whole #)# of protons # of neutronsAtomicNumber# of protons# of electrons # of protons
ATOMIC NUMBERThe number of protons in thenucleus of each atom of thatelement.Element# of protons Atomic # (Z)Carbon66Phosphorus1515Gold7979
Changing Protons makes anewELEMENTwith a NEW name!
Sodium has 11 protons.Take one away and ithas 10 and is no longersodium it is now Neon!
WHICH OF THE FOLLOWING DETERMINESTHE IDENTITY OF AN ATOM?A.B.C.D.E.Number of protonsNumber of electronsNumber of neutronsTotal number of protons and neutronsTotal number of protons and electrons
WHICH OF THE FOLLOWING DETERMINESTHE IDENTITY OF AN ATOM?A.Number of protonsB.C.D.E.Number of electronsNumber of neutronsTotal number of protons and neutronsTotal number of protons and electrons
MASS NUMBERThe number of protonsand neutrons in thenucleus of an isotope.Mass # p n0NuclideOxygen - 18Arsenic - 75Phosphorus - 31p n0e-Mass #8108183342337515161531
Changing Neutrons makesa newISOTOPE
ISOTOPESAtoms of the same element having differentmasses due to varying numbers of ritium)112Nucleus
AVERAGE ATOMIC MASSESThe average of all the naturally occurringisotopes of that element.Composition ofthe nucleus6 protons6 neutronsIsotopeSymbolCarbon-1212CCarbon-1313C6 protons7 neutrons1.11%Carbon-1414C6 protons8 neutrons 0.01%Carbon 12.011% in nature98.89%
Changing Electrons makesa newION
IONSWhen you change the number of electrons in anatom.# of P to# of e-ChargeExamplesymbolLostCationelectronsP e-positiveCa2 GainedAnionelectronsP e-negativeN3-IonChange
SodiumNormally:11 protons 1111 electrons -11zero charge0
SodiumTake away:an electron11 protons 1110 electrons -10positive charge 1
OxygenNormally:8 protons 88 electrons -8zero charge 0
OxygenGive 2 extra:electrons8 protons 810 electrons -10negative charge -2
-0charge -1charge -- 1charge-2charge
IONS!OxygenSodiumO-2Na 1NegativePositiveAnionCationGainedelectronsTook awayelectrons
Need some extra explanation?What are Isotopes Videohttps://www.youtube.com/watch?v EboWeWmh5PgWhat are Ions Videohttps://www.youtube.com/watch?v WWc3k2723IM
LINK TO YOUTUBE VIDEO OF PRESENTATIONhttps://youtu.be/vDzHcK1MUHo
John Dalton. DALTON’S ATOMIC THEORY (1808) 2) Atoms of a given element are identical in size, mass, and other properties John Dalton. DALTON’S ATOMIC THEORY (1808) 3) Atoms of different elements differ in . DALTON’S BILLIARD BALL MODEL John Dalton. MODERN ATOMIC THEORY .
Physical & Chemical Properties Chemical & Physical Changes Matter Obj. 2.1.2 Atomic Structure Isotopes Matter Obj. 2.1.2 Rate Atomic Structure Obj. 2.1.4 Matter Obj. 2.1.2 Phase Change Test Matter Matter Atomic Structure Obj. 2.1.4 Atomic Structure Obj. 2.1.4 Atomic Structure Structure Atomic Structure Obj.
b) 21Neon has three isotopes, 20Ne, Ne and 22Ne. The percentage of each in order is 90.48%, 0.27% and 9.25%. Calculate the relative atomic mass of neon. c) Element Y exists as two naturally occurring isotopes, Y-51 and Y-52. Given that Y-51 has a natural abundance
1. describe previous atomic theories and compare to our modern understanding of the atom (4.1) 2. distinguish among protons, electrons, and neutrons in terms of mass and charge. (4.2) 3. describe the structure of the atom. (4.2) 4. explain why isotopes differ and why atomic masses are not whole numbers. (4.3) 5. understand how atomic mass is .
1) Magnesium has three naturally-occurring isotopes: Magnesium-24 (78.99%), Magnesium-25 (10.00%), and Magnesium-26 (11.01%). Calculate the atomic mass (in amu) of magnesium. Max Time: 4 min 2) Silicon has three naturally-occurring isotopes: Silicon-28, Silicon-29, and Silicon-30. Their natural abundances
radii to three isotopes [20]. This third isotope is required for the calibration of the atomic parameters. Alternatively, the atomic parameters could also be adjusted to match the trend of the silver isotopes to Pd and Cd, as was done to produce the inset of Fig. 3. This biased approach may h
Isotopes - Chlorine (Cl) also has two naturally occurring isotopes: one has 18 neutrons and represents 75.78% of all naturally occurring chlorine the other has 20 neutrons and represents the remaining 24.22% of all naturally occurring chlorine. - Magnesium (Mg) has three naturally occurring isotopes: one
Two versions of LIMS for Light Stable Isotopes are available. LIMS for Light Stable Isotopes version 7.0 operates on the Microsoft Windows 95 or Windows NT 4.0 (or higher) platforms under Access 97. LIMS for Light Stable Isotopes version 1.4, runs on the Microsoft Windows 3.1 or the Windows for Workgroups 3.11 platform under Microsoft Access 2.0.
52 Scientific American April 1997 Black Holes and the Information Paradox BLACK HOLE’S SURFACE looks to Windbag (in the spaceship) like a spheri-cal membrane, called the horizon. Wind-bag sees Goulash, who is falling into the black hole, as being slowed down and flattened at the horizon; according to string theory, Goulash also seems to be spread all over it. Thus, Windbag, who represents .
