Who thought everything was made from fire, earth, air, and water?​

What is the oxidation half-reaction for this unbalanced redox equation? cr2o72– + fe2+ → cr3+ + fe3+ cr3+ → cr2o72– cr2o72– → cr3+ fe3+ → fe2+ fe2+ → fe3+?

Use the periodic table and your knowledge of isotopes to complete these statements. when polonium-210 emits an alpha particle, the child isotope has an atomic mass of 1-131 undergoes beta-minus decay. the chemical symbol for the new element is fluorine-18 undergoes beta-plus decay. the child isotope has an atomic mass of done intro donne

Ketones are converted to enolates on treatment with base. draw the structures of the enolates formed when the ketone shown is treated with either lda or tert-butoxide. include all lone pairs of electrons and nonzero formal charges. do not include counter ions.