Zadanie 2b
(i) State which two further mass measurements are needed to find the oxide composition. (ii) Outline how these measurements give the mass of oxygen removed from the sample.
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(i) State which two further mass measurements are needed to find the oxide composition. (ii) Outline how these measurements give the mass of oxygen removed from the sample.
Suggest why the amount of oxygen per mole of iron calculated from the results is often lower than the true value, and how this error could be reduced.
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(i) A dilute aqueous solution of sodium chloride is electrolysed using inert electrodes. Give the half-equation for the process at the anode and the half-equation for the process at the cathode. Use section 19 of the data booklet. (ii) Identify the product at…
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Chromium(III) oxide, Cr2O3, is a hard ceramic used as an abrasive and as a wear-resistant coating. Outline the bonding in chromium(III) oxide and its electrical conductivity in the solid state. Use sections 9 and 17 of the data booklet.
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