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(i) 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. (ii) The volume of the reactor containing the equilibrium…
(i) Outline the way in which ammonia behaves as a Lewis base during the formation of the complex ion [Ag(NH3)2]+(aq). (ii) Determine the pH at 298 K of an aqueous ammonia solution of concentration 0.180 mol dm−3. Use section 1 of the data…
Which diagram shows the electron configuration of an oxygen atom in its ground state? A. Diagram A B. Diagram B C. Diagram C D. Diagram D
(i) Write a balanced equation, with state symbols, for this reaction. (ii) Deduce which of the two reactants runs out first, that is, which one limits the reaction. Use sections 1, 4 and 7 of the data booklet. (iii) Calculate the volume, in dm3,…
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. (i) Sketch, on the same axes, the curve you would expect if the experiment were repeated with the acid…
Magnesium carbonate and magnesium chloride are ionic compounds. (i) The Born-Haber cycle for magnesium chloride, MgCl2, is shown with three boxes left empty. Annotate the cycle by writing the name of the process, or the formulas of the species present…
The successive ionization energies of an element are plotted against the number of the ionization. What is the group number of the element? A. 2 B. 3 C. 13 D. 14
The structure of galantamine is shown below. (i) State the name of the functional group that contains the nitrogen atom. (ii) Outline the effect of this functional group on the pH of water in which galantamine is dissolved, giving the direction of the change…
A chemist treated 22.99 g of galantamine with sulfuric acid to make the sulfate salt: 2 C17H21NO3 + H2SO4 → (C17H22NO3)2SO4 The mass of salt isolated was 24.65 g. Determine the percentage yield of the salt. Use section 7 of the data booklet.
The mass spectrum of a sample of an element shows two peaks. What is the relative atomic mass of the element? A. 6.1 B. 6.5 C. 6.9 D. 7.0