OCR A Specimen Paper 1 Q16

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10 SECTION B Answer all the questions. 16 Ammonia is a gas with covalently-bonded molecules consisting of nitrogen and hydrogen atoms. (a) Show the electron configuration of a nitrogen atom using electron-in-box diagrams. Label each sub-shell. 1s[2] N2(g) + 3H2(g) 2NH3(g) H = 92 kJ mol1 Equation 1 (b) Ammonia can be made from the reaction of nitrogen and hydrogen in the Haber process. Specimen What effect will increasing the temperature have on the composition of the equilibrium mixture and on the value of the equilibrium constant? Explain your answer.[2]OCR 2014 H432/01<br /> 11 (c) A chemist mixes together 0.450 mol N2 with 0.450 mol H2 in a sealed container. The mixture is heated and allowed to reach equilibrium. At equilibrium, the mixture contains 0.400 mol N2 and the total pressure is 500 kPa. Calculate Kp. Show all your working. Include units in your answer. Specimen Kp =units[5]OCR 2014 H432/01 Turn over<br /> 12 (d) A chemical company receives an order to supply 1.961010 dm3 of ammonia at room temperature and pressure. The Haber process produces a 95.0% yield. Calculate the mass of hydrogen, in tonnes, required to produce the ammonia. Give your answer to three significant figures. required mass of hydrogen =tonnes [3] (i) Hydrazine, N2H4, is used as a rocket fuel. Hydrazine can be prepared from the reaction of ammonia with sodium chlorate(I). There are two other products in the reaction. Write an equation for this reaction. Specimen (ii) Using the electron pair repulsion theory, draw a 3-D diagram of a molecule of hydrazine. Predict the HNH bond angle around each nitrogen atom. (e) [1] HNH bond angle:[2]OCR 2014 H432/01<br /> 13 BLANK PAGE SpecimenOCR 2014 H432/01 Turn over<br />

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