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The copper(II) ion, Cu2+, forms a variety of coloured complexes. (i) Outline, with a reason, why solutions containing [Cu(H2O)6]2+ ions are blue. Use section 15 of the data booklet. (ii) State the type of bond between the copper(II) ion and…
Successive ionization energies of an element: Which element has these successive ionization energies? A. Sodium B. Magnesium C. Aluminium D. Silicon
Calculate the pH of a 0.125 mol dm−3 solution of sodium hydroxide.
A sample of the sodium hydroxide solution is gradually added to 25.0 cm3 of an aqueous solution of an unknown organic acid, producing the following pH curve. Calculate the concentration of the unknown organic acid.
The titration curve below was obtained when the sodium hydroxide solution was added to 25.0 cm3 of the unknown organic acid in part (b). State, with a reason, which indicator would be appropriate for this titration, using section 18 of the data booklet.
Suggest two different mixtures, each prepared from the unknown organic acid, that would produce a buffer solution.
The first three ionization energies of elements X and Y are plotted below. Which pair of elements is X and Y? In each option the element X is given first and the element Y second. A. Al, Na B. Mg, Al C. Na, Mg D. Mg, Na
Compound X is a flavour compound that occurs in many plants. Its structure is shown below. (i) State the IUPAC name of compound X. (ii) State the name of the functional group represented by the C=O bond itself in compound X. (iii) Predict the size of the H–C=O…
1-Bromobutane, CH3CH2CH2CH2Br, is used as a solvent and as a building block for other organic compounds. (i) Predict the organic compound produced from 1-bromobutane and hydroxide ions. (ii) Deduce the type of reaction in (i) and give a reason for your…
Methane reacts with bromine gas in the presence of UV radiation to produce brominated hydrocarbons. (i) Explain, using an equation, how a bromine molecule undergoes homolytic fission. (ii) Using two equations, explain the propagation steps in the substitution…