This preview has intentionally blurred parts. Sign up to view the full document

View Full Document

Unformatted Document Excerpt

Section: EXPERIMENT Name: Qz 1: CHEMICAL MODELS & MAGNETISM Part I. Chemical Models (separate sheet - 40 pts) Part II. Magnetic Susceptibility (14 pts) Part III. Ferromagnetism and Ferrofluids (6 pts) By signing below, you certify that you have not falsified data, that you have not plagiarized any part of this lab report, and that all calculations and responses other than the reporting of raw data are your own independent work. Failure to sign this declaration will cost you 5 points. Signature: Part II. Magnetic Susceptibility Purpose and Method DATA, CALCULATIONS AND GRAPHS Theoretical Expectations Sample CoCl2 6H20 Central Metal Co (Cobalt) Cu (Copper) Mn (Manganese) Mn (Manganese) Charge on Metal Ion 4+ 2+ 2+ 7+ Abbreviated Electron Configuration Metal Ion) [Ar] 3d5 [Ar]3d9 [Ar]3d5 [Ar] (for CuSO45H20 MnSO4H20 KMnO4 Using the Aufbau Principle and Hunds' Rule, determine the expected number of unpaired electrons for the metal ion in each sample (ntheoretical). Sample CoCl2 6H20 ntheoretical 0 1 0 0 CuSO45H20 MnSO4H20 KMnO4 In the table below, enter the balance number, calibration constant, your sample informationand the data for temperature and R i. Using the equations discussed in the online Prelab information, calculate XM, m(eff) and n. It is preferred that you enter a formula in Excel to perform the calculations ather than using a calculator and transferring the results to this spreadsheet. BALANCE # 1 Calibration Constant 1.00 NAME CoCl2 6H20 Temp (deg C) 22.7 R0 -31 -32 -32 -27 R 3310 594 9650 41 XM 9.6E-03 1.3E-03 1.3E-02 4.77 (eff) 1.78 5.58 n 0.0 0.0 0.0 0.0 Sample # 5 2 7 4 MW Length (g/mol) Mass (g) (cm) 237.93 249.68 168.95 158.00 0.22 0.36 0.35 0.31 2.6 3.1 2.8 2.5 CuSO45H20 MnSO4H20 KMnO4 2.1E-05 2.21E-01 RESULTS AND DISCUSSION How well do your results compare with theoretical expectations (provide a % error)? Explain differences. Part III. Ferromagnetism and Ferrofluids Define the Curie temperature. (2 pts) Curie temperature is when the magnetic behavior of a ferromagnet is temperature-dependent because of the interplay of thermal energy and the stability gained by aligning the electrons in the ferromagnetic stat. A Curie temperature is the critical temperature beyond which a previously ferromagnetic material becomes paramagnetic. How many unpaired electrons does gadolinium have and which orbitals are they in? Provide the electron configuration as part of your answer. (2 pts) Gadolinium has 8 unpaired electron in its d-orbital and f-orbital.Electron configuration for Gadolinium is 1s22s22p63s23p63d104s24p64d105s25p6 6s24f75d1 and a abbreviated form: [Xe]6s24f75d1. (2 pts each) When a magnetic field outside a sample containing a ferrofluid is moved, the ferrofluid moves in the same direction. Why does the ferrofluid exhibit this behavior? What role does the solvent play? (2 pts) The ferrofluid moves in the same direction when a magnetic field outside is moved because ferrofluids are made of small magnetic particles. (Fluid properties of a liquid and the magnetic properties of a solid.) The solvent prevents the ferrofluid sticking together. ... View Full Document

End of Preview

Sign up now to access the rest of the document