Several simple copper and cobalt compounds were measured for their magnetic susceptibility using a magnetic balance. These compounds were: [Cu$_4$(OH)$_6$SO$_4$]$_n$ 1, [Cu$_2$(CH$_3$COO)$_4$(H$_2$O)$_2$] 2, [Cu$_2$(C$_5$H$_{11}$COO)$_4$]$_n$ 3, [Cu$_2$(C$_8$H$_{17}$COO)$_4$]$_n$ 4, [CuCl]$_n$ 5, [Co(CH$_3$COO)$_2$(H$_2$O)$_4$] 6, [Co(NH$_3$)$_6$](Cl)$_3$ 7 and Na$_3$[Co(NO$_2$)$_6$] 8. Some of these compounds were syntesized, some were isolated in the student laboratory courses, and some were commercial. IR spectra were also measured to check the purity of these compounds and for the types of chemical bonds present. The formulae of these compounds were checked against the reported structural descriptions. Calculated effective magnetic moments are consistent with the oxydation states of 1-4 having Cu(II) and exhibit antiferromagnetic coupling. On the other hand, Co(II) was confirmed for 6, while compounds 7 and 8 contain Co(III) species. All cobalt compounds confirm that their metal ions are magnetically isolated. The color and magnetic susceptibility of copper compound 5 suggest that an oxidation took place with at least a part of the sample from Cu(I) to Cu(II).
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