Karteikarten
Atomic model
Karten in diesem Stapel (28)
- 1Formula to determine the maximum number of electrons an orbit can accommodate.2n²
- 21amu = ..........934eV or 931eV
- 3Radius: 1. Atom 2. Nucleus1. 10⁻¹⁰m
2. 10⁻¹4 m/10 to the power minus 15 m - 4Radius: 1. electron 2. proton 3. neutron1. 2.5X10 to the power minus 14 m
2. 1.2X10 to the power minus 14 m
3. 1.2X10 to the power minus 14m - 5Charge: 1. electron 2. proton 3. neutron1. - 1.60X10 to the power minus 19
2. 1.60X10 to the power minus 19
3. neutral - 6Mass: 1. electron 2. proton 3. neutron1. 9.11X10 to the power minus thirty one kg
2. 1.672X10 to the power minus 27 kg
3. 1.675X10 to the power minus 27 kg - 7Mass in amu: 1. proton 2. neutron1. 1.00727663
2. 1.0086654 - 8How the particle is generated: 1. electron 2. proton 3, neutron1. Cathode Ray
2. positive rays from hydrogen gas
3. Bombardment of B, Be, Li etc by alpha particles - 9Discovery: 1. electron 2. proton 3. neutron1. Thomson, 1897
2. Rutherford, 1911
3. Chadwick, 1932 - 10Atomic models1. Dalton 1803
2. Thomson, 1898
3. Rutherford, 1911
4. Bohr, 1913
5. Bohr - Summerfield, 1916
6. Wave mechanical, 1924 (Louis de Broglie) - 11Othernames for atom models: 1. Thomson's Plum-pudding model 2. Rutherford's1. Raisin-pudding model or watermelon model
2. solar model or planetary model - 12The thickness of the gold plate in alpha scattering experiment0.004mm / 0.0004cm
- 13The substance used to observe the alpha particles is the scattering experimentZnS
- 14Rutherford's atom model (5)1. A very small central nucleus
2. Most of the atom is empty space
3. The nucleus is positively charged. Different atoms have different positive charges because of different number of protons.
4. The no. of protons = the no. of electrons.
5. Electrons orbit the nucleus like planets orbit the sun - 15Limitations of Rutherford's atom model (6)1. Electrons are compared to planets but planets are neutral and electrons are negative.
2. Planets are attracted by gravity, electrons are attracted by electrostatic force.
3. Clark Maxwell - electrons will spiral into the nucleus.
4. Did not give the shape of the orbitals.
5. Cannot explain the line spectrum of hydrogen.
6. Cannot explain how electrons orbit in multi-electron atoms. - 16Forces acting on a moving electronElectrostatic force of attraction and centrifugal force due to the motion of the electrons. These two forces are equal and opposite.
- 17Bohr's atom model postulates1. Discrete energy levels.
2. Angular momentum, mvr=nh/2π
3. Energy radiations - 18Bohr's frequency conditionE = E2-E1 = hf
This is the equation which shows that energy is radiated/absorbed when an electron moves between orbits. - 19Radius of hydrogen atomRn=n²r₁ ,
r₁=0.529X10⁻¹⁰m = 0.529Å
r₁ is Bohr's first orbit or radius of hydrogen atom. - 20Equation relating potential energy and kinnetic energyEp= -2Ek
- 21Energy equationEn=E₁/n²
E₁ is the lowest energy state or the energy of ground state
E₁=13.6eV - 22Limitations of Bohr's atom model (9)1. Cannot explain the spectral of multi-electron atoms.
2. Cannot explain the intensities of the spectral lines.
3. Cannot explain the fine structures of the spectral lines.
4. Zeeman effect - splitting of spectral lines due to magnetic field.
5. Starck effect - splitting of spectral lines due to electric field.
6. He said that the orbits are planar/circular but they are actually 3D.
7. Heisenberg uncertainty principle
8. Cannot explain chemical combinations and shape of molecules.
9. Does not recognize the wave property of electron. - 23X rays can be produced fromCathode ray
- 24Composite particlesDeuteron and Alpha
- 25Permanent Fundamental particlesProtons, neutrons and electrons
- 26Half life of Uranium4500 million years
- 271 dalton =1.6605 X 〖10〗^(-27) kg or
1.6605 X 〖10〗^(-24)g - 28Penetrating power of gamma rays is ______ than X raysmore
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- Beschreibung
- University Admissions Chemistry Karteikarten am Atomic model, erstellt von Rannia Shehrish am 21/08/2015.
- Erstellt von
- Rannia Shehrish
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