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Pentan-2-ol can form by reacting pent-1-ene with water in the presence of an acid catalyst. CH2=CHCH2CH2CH3(g) + H2O(l) → CH3CH(OH)CH2CH2CH3(aq) ΔH⊖ = −84 kJ mol−1 (i) The first step of the mechanism for the formation of…
Pentan-2-ol will react with acidified potassium dichromate, K2Cr2O7, which is an oxidizing agent. (i) State the name of the product of this reaction. (ii) Explain how infrared spectroscopy could be used to distinguish between pentan-2-ol and the product…
Which species has the ground state electron configuration [Ar] 3d8? A. Cu2+ B. Zn2+ C. Ni D. Ni2+
Outline why a standard solution of potassium manganate(VII) was needed for this analysis.
Suggest why diluting the standard solution was necessary.
State two items of glassware that the dilution required.
The titration was carried out using a burette, a volumetric pipette and a conical flask. State which of the three items should be rinsed with the solution it will hold, and which only with distilled water.
(i) The diagram shows the burette scale at the end of trial 4. The solution is deep purple, so the reading is taken at the top of the liquid. Determine the final burette reading for trial 4 and complete the table. (ii) Suggest, with a reason, whether more…
Colorimetry is an alternative technique for determining concentration. Iron(II) ions can be converted to a red complex ion by adding 1,10-phenanthroline. (i) Outline why the concentration of iron(II) in a solution can be measured by colorimetry after this…
(i) Describe the structure of solid magnesium and state the forces that hold it together. (ii) Explain why a piece of magnesium can be hammered into a new shape without breaking. (iii) Explain why the melting point of magnesium is higher than that of sodium.…