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Glycine, H2NCH2COOH, loses a proton from its carboxyl group in alkaline solution to form the glycinate ion. The glycinate ion can bond to a copper(II) ion through two of its atoms, so it acts as a bidentate ligand. Explain how a glycinate ion bonds to a…
Naturally occurring bromine has Ar = 79.90 and contains only the isotopes 79Br and 81Br. What percentage of the atoms are 81Br? A. 10 % B. 45 % C. 55 % D. 90 %
(i) Calculate the enthalpy change for this reaction, using section 13 of the data booklet and the values given below. (ii) Outline why the entropy change of this reaction is expected to be small. (iii) Ignore the entropy change. Use your answer to (i) together…
Deduce the shapes of the CO2 and H2O molecules and explain why they differ.
Iron has a number of natural isotopes. A sample of iron was enriched in to produce a mixture with the following composition: (i) Calculate the relative atomic mass of the enriched sample, giving your answer to two decimal places. (ii) Natural…
A student electrolysed aqueous silver nitrate between two silver electrodes, as shown. Each electrode was washed, dried and weighed before and after the electrolysis. Suggest why the mass gained by the cathode is a less accurate measure of the amount of silver…
The first three ionization energies of two elements, X and Y, are given in the table. Which pair of elements are X and Y, in that order? A. Aluminium and magnesium B. Magnesium and aluminium C. Sodium and magnesium D. Sodium and aluminium
Outline the nature of the electrostatic attraction that holds together the crystal structure of solid aluminium.
Aluminium is produced industrially by the electrolysis of aluminium oxide dissolved in molten cryolite, as shown in the diagram. (i) Outline why the molten mixture is considered to be an electrolyte. (ii) Identify the electrode at which aluminium forms and…
Aluminium forms a chloride, AlCl3. (i) Draw the Lewis (electron dot) structure of the AlCl3 molecule. (ii) Outline why the Lewis structure of AlCl3 is an exception to the octet rule.