SASS Chem Ammonia Topical

_______________________________________________________________________________________________________________________________________________________________________________________ Page 1 ST ANDREW’S SECONDARY SCHOOL NAME CLASS DATE CHEMISTRY Self-Assessment Topical Test 30 minutes Ammonia INSTRUCTIONS Write your name, class and date on the spaces provided above. Complete all questions on this question paper. You are reminded to revise this topic first before attempting the questions. Multiple-Choice Questions [10 marks] 1 When 1 mol of nitrogen is reacted with 3 mol of hydrogen at 250 atm and 450ºC in the presence of an iron catalyst, less than 2 mol of ammonia is formed. Which of the following best explains this observation? A The pressure used was too low. B The temperature used was too low. C The nitrogen and hydrogen used in the reaction contained impurities. D The reaction of nitrogen and hydrogen to form ammonia is reversible. ( ) 2 In the Haber process, gases are combined directly in a hydrogen to nitrogen ratio of _________. A 1 : 1 B 2 : 1 C 1 : 3 D 3 : 1 ( ) 3 The catalyst used in the Haber process is ____________. A copper B iron C hydrogen chloride D nickel ( ) 4 Ammonia gas is produced when ammonium chloride is heated with ____________. A calcium carbonate B nitric acid C potassium hydroxide D water ( ) Use the following information to answer Questions 5 and 6. The Haber process is used to manufacture ammonia gas. The reaction is exothermic and the chemical equation for the process is: N2(g) + 3H2(g) ⇌ 2NH3(g)

_______________________________________________________________________________________________________________________________________________________________________________________ Page 2 5 What is the effect of increasing the pressure inside the reaction vessel on the rate of production and the yield of ammonia gas? ( ) 6 What is the effect of increasing the temperature inside the reaction vessel on the rate of production and the yield of ammonia gas? 7 Which of the following statements is not true of the Haber process? A The raw material, nitrogen gas, is obtained from the cracking of petroleum. B Unreacted nitrogen and hydrogen are recycled and transferred back into the converter. C Nitrogen and hydrogen gases are compressed at 250 atm during the process. D Liquid ammonia is the product of the Haber process. ( ) 8 Which of the following statements are true of the Haber process? 1 An increase in pressure increases the speed of reaction. 2 An iron catalyst is used to increase the yield of ammonia. 3 A high temperature of 450ºC is used to increase the yield of ammonia. 4 A relatively low pressure of 250 atm is used because it is c