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Beryllium metal is produced by the electrolysis of beryllium chloride, BeCl2, dissolved in molten sodium chloride. (i) Write the half-equation for the process at the electrode where beryllium metal is produced. (ii) Calculate the atom economy of this…
Graphene, a single layer of carbon atoms, is used to reinforce plastics and metals. Outline why graphene is so strong and rigid.
A gas sample gave the experimental results below. Which expression gives the molar mass of the gas, in g mol−1? Ideal gas constant R = 8.31 J K−1 mol−1, PV = nRT A. B.…
State the oxidation state of manganese in the permanganate ion, MnO4−.
A voltaic cell was constructed from an iron(II) sulfate/iron half-cell and a copper(II) sulfate/copper half-cell, connected by a salt bridge and, externally, by a wire. (i) Outline why electrons flow from the iron half-cell to the copper half-cell when the two…
Brass is an alloy of copper and zinc. Explain why brass is harder and stronger, but a poorer conductor of electricity, than pure copper.
The concentration of copper(II) ions in a sample of pond water is determined with a colorimeter. The absorbance of standard solutions of known concentration is measured and a calibration curve is plotted. Sketch the typical shape of the calibration curve on…
The pressure p of a fixed mass of an ideal gas was measured at constant temperature for several different volumes V. Which graph shows p plotted against 1/V? A. Graph A B. Graph B C. Graph C D. Graph D
Tellurium has atomic number 52. Using the position of tellurium in the periodic table, deduce two features of its electron configuration.
Outline why copper is malleable.