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The diagram shows an unlabelled voltaic cell for the reaction: Ni(s) + 2 Ag+(aq) → Ni2+(aq) + 2 Ag(s) (i) Identify, using species from the equation, what W, X, Y and Z are, and state the direction of electron flow in the external circuit. (ii) Write the…
Successive ionization energies of an element, Z, are shown. What energy, in kJ mol−1, is required to convert one mole of gaseous atoms of Z into the ions that Z forms in its ionic compounds? A. 2700 B. 4500 C. 5100 D. 16 700
(i) Deduce the structural formula and the empirical formula of B. (ii) Explain, with reference to Le Châtelier’s principle, the effect on the yield of B of using dilute rather than concentrated sulfuric acid as the catalyst. (iii) Compound A has a lower molar…
Bromine water is added to compound A. Describe the change observed.
Which quantities are different between the species and ? A. Number of protons only B. Number of protons and neutrons only C. Number of neutrons and electrons only D. Number of protons, neutrons and electrons
A sample of coal contains 1.20 % sulfur by mass. Calculate the amount, in mol, of sulfur dioxide produced when 400.0 g of this coal undergoes complete combustion. S(s) + O2(g) → SO2(g)
Some of the sulfur dioxide released is oxidized in the atmosphere to sulfur trioxide, SO3. Write an equation that shows how sulfur trioxide produces acid rain.
Deduce the Lewis (electron dot) structure of sulfur trioxide.
A student compares the rate of the reaction between magnesium ribbon and dilute hydrochloric acid at different temperatures by timing how long it takes for a piece of ribbon to dissolve completely. Mg(s) + 2 HCl(aq) → MgCl2(aq) + H2(g) Suggest two…
Coal-fired power stations release carbon dioxide and sulfur oxides. Discuss two different measures that could reduce the environmental impact of generating electricity from coal.