Chemistry_Grade_10-12 (1).pdf

Haber was jewish by birth but converted from judaism

Info icon This preview shows pages 387–390. Sign up to view the full content.

Haber was Jewish by birth, but converted from Judaism in order to be more accepted in Germany. Despite this, he was forced to leave the country in 1933 because he was Jewish ’by definition’ (his mother was Jewish). He died in 1934 at the age of 65. Many members of his extended family died in the Nazi concentration camps, possibly gassed by Zyklon B. 373
Image of page 387

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

19.7 CHAPTER 19. GLOBAL CYCLES: THE NITROGEN CYCLE - GRADE 10 Preparation of nitric acid (HNO 3 ) Nitric acid is used to prepare fertilisers and explosives. The industrial preparation of nitric acid is known as the Ostwald process . The Ostwald process involves the conversion of ammonia into nitric acid in various stages: Firstly, ammonia is heated with oxygen in the presence of a platinum catalyst to form nitric oxide and water. 4 NH 3 ( g ) + 5 O 2 ( g ) 4 NO ( g ) + 6 H 2 O ( g ) Secondly, nitric oxide reacts with oxygen to form nitrogen dioxide. This gas is then readily absorbed by the water to produce nitric acid. A portion of nitrogen dioxide is reduced back to nitric oxide. 2 NO ( g ) + O 2 ( g ) 2 NO 2 ( g ) 3 NO 2 ( g ) + H 2 O ( l ) 2 HNO 3 ( aq ) + NO ( g ) The NO is recycled, and the acid is concentrated to the required strength by a process called distillation . Preparation of ammonium nitrate Ammonium nitrate is used as a fertiliser, as an explosive and also in the preparation of ’laughing gas’ which is used as an anaesthetic. Ammonium nitrate is prepared by reacting ammonia with nitric acid: NH 3 + HNO 3 NH 4 NO 3 Activity :: Debate : Fertiliser use Divide the class into two groups to debate the following topic: Increasing the use of artificial fertilisers is the best solution to meet the growing food needs of the world’s human population. One group should take the position of agreeing with the statement, and the other should disagree . In your groups, discuss reasons why you have the opinion that you do, and record some notes of your discussion. Your teacher will then explain to you how to proceed with the debate. 19.7 Summary Nitrogen is essential for life on earth, since it forms part of amino acids , proteins and nucleic acids . The atmosphere is composed mostly of nitrogen gas, but the gas is inert , meaning that it is not available to living organisms in its gaseous form. The nitrogen cycle describes how nitrogen and nitrogen-containing compounds are changed into different forms in nature. 374
Image of page 388
CHAPTER 19. GLOBAL CYCLES: THE NITROGEN CYCLE - GRADE 10 19.7 The nitrogen cycle consists of three major processes: nitrogen fixation , nitrification and denitrification . Nitrogen fixation is the conversion of atmospheric nitrogen into compounds such as ammonia, that are more easily used. Nitrogen can be fixed biologically through the actions of bacteria , industrially through the Haber-Bosch process or by lightning .
Image of page 389

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

Image of page 390
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern