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The rate of the reaction can be followed by measuring the volume of carbon dioxide collected as time passes. The graph shows the results obtained at 20 °C. Sketch, on the same axes, the curve you would expect if the experiment were repeated with the acid at a…
When an electric discharge is passed through hydrogen gas at low pressure, the emitted light forms a line emission spectrum: a series of separate, sharp lines that converge as the frequency increases, rather than a continuous band of colour. What does this…
(i) Determine, using a suitable construction drawn on the graph, the initial rate at which CO2(g) is released, in g s−1, in the reaction with 1.20 mol dm−3 HNO3(aq). (ii) Determine the average rate of release of…
For the runs with 0.40 and 0.80 mol dm−3 HNO3(aq), suggest which reactant, CaCO3(s) or HNO3(aq), was the limiting reagent. Give a reason for your answer.
Suppose carbonyl dibromide were made by a free-radical chain reaction of carbon monoxide, CO, with bromine vapour, Br2, started by ultraviolet light. The questions below treat this hypothetical route with the bond-enthalpy model. (i) Write an…
In moist air carbonyl dibromide is slowly hydrolyzed: Br2CO(g) + H2O(g) → CO2(g) + 2 HBr(g) (i) Suggest a method of monitoring the progress of this reaction at constant temperature so that its rate can be determined. (ii) Outline two reasons why a…
What volume of propane gas, in cm3, must be burned completely in oxygen to give 90 cm3 of carbon dioxide, all volumes being measured at the same temperature and pressure? C3H8(g) + 5 O2(g) → 3 CO2(g) + 4 H2O(g) A. 18 B. 30 C. 90 D.…
An equilibrium mixture in a 25.0 dm3 reactor at 500 °C contains 15.0 mol N2, 22.5 mol H2 and 5.25 mol NH3. Calculate the equilibrium constant, K, for the reaction.
The volume of the reactor containing the equilibrium mixture described in 3a is suddenly increased at constant temperature. Sketch, on the axes below, how the concentration of hydrogen changes with time until the new equilibrium is established.
Which row shows the gas and the conditions under which its behaviour is closest to that of an ideal gas? A. Hydrogen fluoride, HF, at high pressure and low temperature B. Methane, CH4, at high pressure and low temperature C. Hydrogen fluoride,…