CHEM10006 Lecture Notes - Lecture 16: Nernst Equation, Glass Electrode, Oxidation State

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In binary compounds assign numbers in priority of most electronegative atom, then work out the oxidation number for the other atom. An oxidant is reduced, a reductant is oxidised. Add h20 and h+ to balance oxygen and hydrogen respectively. Check oxidation numbers to see which species is being oxidised (oxidation number will decrease) and which species is being reduced (oxidation number will increase) Redox reaction in galvanic cells release energy, solution becomes warmer. Reduction potential and oxidising strength: remember the backwards z for a spontaneous reaction. Whe(cid:374) (cid:449)e do(cid:374)(cid:859)t ha(cid:448)e sta(cid:374)da(cid:396)d (cid:272)o(cid:374)ditio(cid:374)s, use the ne(cid:396)(cid:374)st e(cid:395)uatio(cid:374) to tell us (cid:449)hat the (cid:272)ell potential will be. When a battery is dead (cell potential is zero) the battery is at equilibrium. In the nernst equation, overall cell potential is zero, we can solve for equilibrium constant. If the half-cells are the same (ni/ni2+) there will still be a cell potential due to the difference i(cid:374) (cid:272)o(cid:374)(cid:272)e(cid:374)t(cid:396)atio(cid:374).