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Potassium bromide, KBr, forms a three-dimensional lattice of ions. (i) Demonstrate how the electronegativity values and bonding triangle in sections 9 and 17 of the data booklet support an ionic model for this solid. (ii) Outline the nature of the…
Sodium metal is manufactured by the electrolysis of molten sodium chloride. (i) Outline why sodium can be produced by electrolysis rather than by reduction with carbon. (ii) State the half-equation for the formation of sodium during the electrolysis.
8.00 mol of ammonia are mixed with 8.00 mol of oxygen. The equation for the reaction that occurs is shown below. 4 NH3(g) + 5 O2(g) → 4 NO(g) + 6 H2O(g) What is the amount, in mol, of nitrogen(II) oxide, NO, produced, assuming that the reaction goes to…
(i) State one environmental problem caused by acid rain. (ii) Write an equation for the reaction of sulfur trioxide, SO3, with water in the atmosphere, in which an acid forms.
Potassium oxide, 0.0150 mol, was dissolved in water and the solution was made up to a final volume of 250.0 cm3. (i) Write a balanced equation for the reaction of potassium oxide with water. (ii) Calculate the pH of the solution.
Hypochlorous acid, HOCl(aq), has Ka = 2.95 × 10−8. (i) Determine the pH of an aqueous solution of hypochlorous acid of concentration 0.150 mol dm−3. (ii) State one assumption you made in the calculation in (i). (iii) State…
Which electron transition produces the line of longest wavelength in the visible region of the hydrogen line emission spectrum? A. Transition A B. Transition B C. Transition C D. Transition D
(i) State the oxidation states of carbon in carbon monoxide and in carbonyl chloride. (ii) For each of CO and Cl2 in the forward reaction, state whether it acts as an oxidizing agent or a reducing agent, and whether it is oxidized or reduced.
(i) Draw the Lewis (electron dot) structure of carbonyl chloride. (ii) Mark the bond polarities on your Lewis structure using the symbols δ+ and δ−. (iii) Explain the shape of the carbonyl chloride molecule and whether it is polar. (iv) State…
Poly(lactic-co-glycolic acid) is a condensation polymer used for dissolving surgical stitches. It is made from two monomers. A short section of the polymer chain is shown; the bonds ending in an asterisk continue the chain. Draw the functional groups needed to…