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Poly(chloroethene) is made from the monomer CH2=CHCl by addition polymerization. Nylon-6,6 is made from the monomers H2N(CH2)6NH2 and HOOC(CH2)4COOH by condensation polymerization. Distinguish between these two types of polymerization by…
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
A dilute aqueous solution of potassium iodide, KI(aq), is electrolysed using inert graphite electrodes, as shown in the diagram. (i) State the direction in which the electrons move in the external circuit, and the direction in which the positive ions and the…
The concentration of dissolved oxygen in a sample of pond water was determined by the Winkler method. The reactions that take place are:…
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.
What is the maximum number of electrons that can occupy the main energy level n = 3? A. 6 B. 9 C. 18 D. 32
State the oxidation state of manganese in the permanganate ion, MnO4−.
(i) Outline why electrons flow from the iron half-cell to the copper half-cell when the two are connected by a wire. Use section 19 of the data booklet. (ii) Formulate equations for the reactions taking place at the anode (negative electrode) and at the…
(i) Calculate the standard cell potential for the voltaic cell. Use section 19 of the data booklet. (ii) Calculate the standard Gibbs energy change, ΔG⊖, in kJ mol−1, for the cell reaction. Use sections 1 and 2 of the data…