(a(i))[4]
Use the information in the table to suggest how pure, dry samples of copper and selenium could be obtained from a mixture of copper powder and selenium powder.
(a(ii))[2]
Ethanol is an organic solvent. Draw the structure of ethanol. Include every atom and every bond.
(a(iii))[1]
Selenium reacts with fluorine to produce selenium(VI) fluoride. Balance the chemical equation for this reaction: Se + ....F$_2$ → SeF$_6$
(b(ii))[2]
One compound in this equation is a pollutant gas that contributes to acid rain. Identify the pollutant gas and state one common source of it.
(c)[1]
Solid hydrated copper(II) sulfate changes into anhydrous copper(II) sulfate when it is heated continuously. Is this an endothermic or an exothermic reaction? Explain your answer.