quantum theory, periodicity and experimental techniques (mass spec/pes/spectrophotometry)

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Quantum Theory, Periodicity and Experimental

Techniques (Mass Spec/PES/Spectrophotometry)

What to study:* Main scientists who contributed to the atomic model (name of experiment)* Quantum numbers (formula and what each quantum number means)* Formulas: (see what is provided in the formula sheet) -- calculating wavelength when energy level changes (R= -2.178 X 10 -18 J ) --calculating energy from wavelength/frequency/c*Electromagnetic spectrum (relative order including visible light/ relationship of λ and frequency)*Rules for orbital diagram and electron configuration (including exceptions)

Vocab*Orbitals *Photon*Isoelectronic *Ionization*Paramagnetic *Electronegativity*Diamagnetic *Electron Affinity*Electron Configuration *Valence e*Noble Gas Config. *Metalloids*Quantum #’s *Hunds Rule*Z effective *Pauli Exclusion*Heisenberg Uncertainty *Aufbau PrinciplePrinciple

Molarity (M) = moles solute

Liter solution

M1V1 = M2V2

Concentration – Moles/L (M)Dilution – M1V1= M2V2

Ex. Create a solution with 10 moles of NaCl in 2 L water. This is your initial solution. Dilute this solution by taking 1L, transfer to a beaker and then add 1L of water. This makes your diluted to have a total new volume of 2 L (1:2 dilution)

Initial Concentration: 10moles/2L = 5 M

1:2 Dilution: (5M) (1L) = M2 (2L) M2 = 2.5 M

Mini Lab: Determine the concentration of food dye using a spectrophotometer

Materials: spec-20, test tubes, cuvets, DI water, Kimwipes, pipets, graduated cylinders

Procedure: The group will be assigned either solution A, B or C. They have to determine proper dilution so the absorbance result will be within the range of the standard graph. The target wavelength is 630 nm.

Absorbance vs. Transmittance

Standard GraphAb

sorb

ance

Concentration (mol/L)

Pre-Lab: Concentration of Food DyeGoal: To determine unknown concentration of food dye based on known concentration from a standard calibration curve

A. Standard1.7 X 10 -4 M

B. ?

Mass Spectrometry

Photoelectron Spectroscopy

Photoelectron Spectroscopy

1 2 3 4 5 6 7 8H 1312He 2372 5250Li 520 7297 11810Be 899 1757 14845 21000B 800 2426 3659 25020 32820C 1086 2352 4619 6221 37820 47260N 1402 2855 4576 7473 9442 53250 64340O 1314 3388 5296 7467 10987 13320 71320 84070F 1680 3375 6045 8408 11020 15160 17860 92010Ne 2080 3963 6130 9361 12180 15240Na 496 4563 6913 9541 13350 16600 20113 25666Mg 737 1450 7731 10545 13627 17995 21700 25662

Ionization Energies in kJ/mol

LAB: Photoelectron Spectroscopy*Make sure to include: Title/ Purpose/ Materials/Questions

Conclusion: *Discuss what information we can get from a PES graph.*Discuss ionization energy of electrons relative to their distance from the nucleus. *Discuss any limitations of the PES graph.

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