1 / 66

iGCSE chemistry Section 5 lesson 4

iGCSE chemistry Section 5 lesson 4. Content. The iGCSE Chemistry course. Section 1 Principles of Chemistry Section 2 Chemistry of the Elements Section 3 Organic Chemistry Section 4 Physical Chemistry Section 5 Chemistry in Society. Content. Section 5

ericnelson
Télécharger la présentation

iGCSE chemistry Section 5 lesson 4

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. iGCSE chemistrySection 5 lesson 4

  2. Content The iGCSE Chemistry course Section 1 Principles of Chemistry Section 2 Chemistry of the Elements Section 3 Organic Chemistry Section 4 Physical Chemistry Section 5 Chemistry in Society

  3. Content Section 5 Chemistry in industry • Extraction and uses of metals • Crude oil • Synthetic polymers • The industrial manufacture of chemicals

  4. d) The industrial manufacture of chemicals 5.22 understand that nitrogen from air, and hydrogen from natural gas or the cracking of hydrocarbons, are used in the manufacture of ammonia 5.23 describe the manufacture of ammonia by the Haber process, including the essential conditions: i a temperature of about 450°C ii a pressure of about 200 atmospheres iii an iron catalyst 5.24 understand how the cooling of the reaction mixture liquefies the ammonia produced and allows the unused hydrogen and nitrogen to be recirculated 5.25 describe the use of ammonia in the manufacture of nitric acid and fertilisers 5.26 recall the raw materials used in the manufacture of sulphuric acid 5.27 describe the manufacture of sulphuric acid by the contact process, including the essential conditions: i a temperature of about 450°C ii a pressure of about 2 atmospheres iii a vanadium(V) oxide catalyst 5.28 describe the use of sulphuric acid in the manufacture of detergents, fertilisers and paints 5.29 describe the manufacture of sodium hydroxide and chlorine by the electrolysis of concentrated sodium chloride solution (brine) in a diaphragm cell 5.30 write ionic half-equations for the reactions at the electrodes in the diaphragm cell 5.31 describe important uses of sodium hydroxide, including the manufacture of bleach, paper and soap; and of chlorine, including sterilising water supplies and in the manufacture of bleach and hydrochloric acid. Lesson 4 d) The industrial manufacture of chemicals

  5. 1. The Haber Process - Ammonia, NH3 The Industrial Manufacture of Chemicals 2. The Contact Process – Sulphuric acid 3. Sodium hydroxide and Chlorine

  6. #1 The Haber Process

  7. #1 The Haber Process What’s this all about?

  8. #1 The Haber Process Plants need nutrients in order to survive. To improve crop yields, farmers spread fertilisers on their fields. These fertilisers contain minerals essential for healthy plant growth.

  9. #1 The Haber Process During World War I, blockades of Germany by the Allies meant that the German farmers could not get any access to natural fertilisers from South America. In order to prevent mass starvation, German chemists developed a process for making ammonia from atmospheric nitrogen.

  10. #1 The Haber Process Fritz Haber developed the first practical process to convert atmospheric nitrogen into ammonia. From ammonia fertilisers could be made. Fertiliser generated from ammonia produced by the Haber process is estimated to be responsible for sustaining one-third of the Earth’s population.

  11. #1 The Haber Process The nitrogen-rich fertiliser ammonium nitrate is used regularly by farmers, and spread in huge quantities on crops around the world.

  12. #1 The Haber Process The Basics!

  13. #1 The Haber Process The Basics! The Haber Process produces ammonia which is needed for making fertilisers.

  14. #1 The Haber Process The Basics! The Haber Process produces ammonia which is needed for making fertilisers. Nitrogen is obtained easily from the air which is 78% nitrogen.

  15. #1 The Haber Process The Basics! The Haber Process produces ammonia which is needed for making fertilisers. Nitrogen is obtained easily from the air which is 78% nitrogen. Hydrogen is obtained from water (steam) and natural gas (methane, CH4)

  16. #1 The Haber Process The Basics! The Haber Process produces ammonia which is needed for making fertilisers. Nitrogen is obtained easily from the air which is 78% nitrogen. Hydrogen is obtained from water (steam) and natural gas (methane, CH4) The Haber Process is a reversible reaction.

  17. #1 The Haber Process The Basics! N2(g) + 3H2(g) 2NH3(g) nitrogen hydrogen ammonia Reversible reaction

  18. #1 The Haber Process The Basics! Industrial Conditions: PRESSURE: 200 atmospheres TEMPERATURE: 450oC CARALYST: Iron

  19. #1 The Haber Process Reaction vessel Trays of iron catalyst 450oC and 200 atm Condenser

  20. #1 The Haber Process H2 and N2 mixed in 3:1 ratio Reaction vessel Trays of iron catalyst 1. The hydrogen and nitrogen are mixed together in a 3:1 ratio 450oC and 200 atm Condenser

  21. #1 The Haber Process H2 and N2 mixed in 3:1 ratio Reaction vessel Trays of iron catalyst 1. The hydrogen and nitrogen are mixed together in a 3:1 ratio 450oC and 200 atm Condenser

  22. #1 The Haber Process H2 and N2 mixed in 3:1 ratio Reaction vessel Trays of iron catalyst 1. The hydrogen and nitrogen are mixed together in a 3:1 ratio 2. Because the reaction is reversible, not all of the N2 and H2 will convert to ammonia. 450oC and 200 atm 3. The NH3 is formed as a gas but as it cools in the condenser it liquefies and is removed. Condenser Liquid ammonia

  23. #1 The Haber Process H2 and N2 mixed in 3:1 ratio Reaction vessel Trays of iron catalyst 1. The hydrogen and nitrogen are mixed together in a 3:1 ratio 2. Because the reaction is reversible, not all of the N2 and H2 will convert to ammonia. 450oC and 200 atm Unused N2 and H2 are recycled 3. The NH3 is formed as a gas but as it cools in the condenser it liquefies and is removed. Condenser 4. The N2 and H2 which didn’t react are recycled in the system Liquid ammonia

  24. Two important reactions involving ammonia

  25. Two important reactions involving ammonia #1 Making Nitric Acid

  26. Two important reactions involving ammonia • A two stage reaction: • Ammonia gas reacts with oxygen over a hot platinum catalyst • 4NH3(g) + 5O2(g) 4NO(g) + 6H2O(g)

  27. Two important reactions involving ammonia • A two stage reaction: • Ammonia gas reacts with oxygen over a hot platinum catalyst • 4NH3(g) + 5O2(g) 4NO(g) + 6H2O(g) A very exothermic reaction, the nitrogen monoxide must be cooled before the next stage.

  28. Two important reactions involving ammonia • A two stage reaction: • Ammonia gas reacts with oxygen over a hot platinum catalyst • 4NH3(g) + 5O2(g) 4NO(g) + 6H2O(g) • The nitrogen monoxide reacts with water and oxygen: • 6NO(g) + 3O2(g) + 2H2O(g)  4HNO3(g) + 2NO(g)

  29. Two important reactions involving ammonia • A two stage reaction: • Ammonia gas reacts with oxygen over a hot platinum catalyst • 4NH3(g) + 5O2(g) 4NO(g) + 6H2O(g) • The nitrogen monoxide reacts with water and oxygen: • 6NO(g) + 3O2(g) + 2H2O(g)  4HNO3(g) + 2NO(g) The nitric acid produced can then be used to make ammonium nitrate fertiliser

  30. Two important reactions involving ammonia #2 Making Ammonium Nitrate fertiliser

  31. Two important reactions involving ammonia This is a simple neutralisation reaction between and acid and an alkali to produce a neutral salt. NH3(aq) + HNO3(aq) NH4NO3(aq) Ammonium nitrate is a particularly good fertiliser because it has nitrogen from two sources – ammonia and nitric acid.

  32. 1. The Haber Process - Ammonia, NH3 The Industrial Manufacture of Chemicals 2. The Contact Process – Sulphuric acid 3. Sodium hydroxide and Chlorine

  33. “describe the manufacture of sulphuric acid by the contact process, including the essential conditions”

  34. The Contact Process Sulphuric Acid H2SO4

  35. The Contact Process Sulphuric Acid H2SO4 Raw materials: sulphur, oxygen, water

  36. The Contact Process Sulphuric Acid H2SO4 Raw materials: sulphur, oxygen, water Conditions: Catalyst (vanadium oxide) Pressure of 2 atmospheres Temperature of about 450oC

  37. The Contact Process Three stage process.

  38. The Contact Process Three stage process. • Preparation of sulphur dioxide • S(s) + O2(g) SO2(g)

  39. The Contact Process Three stage process. • Preparation of sulphur dioxide • S(s) + O2(g) SO2(g) Sulphur is burnt in air (or sulphur ore may be used)

  40. The Contact Process Three stage process. • Preparation of sulphur dioxide • S(s) + O2(g) SO2(g) 2. Preparation of sulphur oxide 2SO(s) + O2(g)2SO3(g)

  41. The Contact Process Three stage process. • Preparation of sulphur dioxide • S(s) + O2(g) SO2(g) may be used) may be used) 2. Preparation of sulphur oxide 2SO(s) + O2(g)2SO3(g) Sulphur dioxide and air pass over vanadium oxide catalyst at 450oC Reaction is exothermic – reversible reaction, so excess air and SO2 ensure good yield of SO3

  42. The Contact Process Three stage process. • Preparation of sulphur dioxide • S(s) + O2(g) SO2(g) 2. Preparation of sulphur oxide 2SO(s) + O2(g)2SO3(g) 3. Preparation of sulphuric acid SO3(s) + H2O (l) H2SO4(l)

  43. The Contact Process Three stage process. • Preparation of sulphur dioxide • S(s) + O2(g) SO2(g) 2. Preparation of sulphur oxide 2SO(s) + O2(g)2SO3(g) 2 stages: (a) the sulphur oxide is dissolved in conc sulphuric acid to produce oleum (b) The oleum is then diluted to give conc sulphuric acid which is 98% acid and 2% water 3. Preparation of sulphuric acid SO3(s) + H2O (l) H2SO4(l)

  44. The Contact Process Three stage process. • Preparation of sulphur dioxide • S(s) + O2(g) SO2(g) 2. Preparation of sulphur oxide 2SO(s) + O2(g)2SO3(g) Sulphur oxide (SO3) cannot be added to water directly since the reaction is violent and dangerous 2 stages: (a) the sulphur oxide is dissolved in conc sulphuric acid to produce oleum (b) The oleum is then diluted to give conc sulphuric acid which is 98% acid and 2% water 3. Preparation of sulphuric acid SO3(s) + H2O (l) H2SO4(l)

  45. Uses of sulphuric acid

  46. 1. The Haber Process - Ammonia, NH3 The Industrial Manufacture of Chemicals 2. The Contact Process – Sulphuric acid 3. Sodium hydroxide and Chlorine

  47. “describe the manufacture of sodium hydroxide and chlorine by the electrolysis of concentrated sodium chloride solution (brine) in a diaphragm cell”

  48. Manufacture of sodium hydroxide and chlorine Sodium hydroxide, chlorine and hydrogen are all produced by the electrolysis of brine (salt – sodium chloride – dissolved in water)

  49. Manufacture of sodium hydroxide and chlorine + - Sodium hydroxide, chlorine and hydrogen are all produced by the electrolysis of brine (salt – sodium chloride – dissolved in water) Titanium anode Steel cathode diaphragm

  50. Manufacture of sodium hydroxide and chlorine + - Sodium hydroxide, chlorine and hydrogen are all produced by the electrolysis of brine (salt – sodium chloride – dissolved in water) Concentrated sodium chloride solution (brine) Titanium anode Steel cathode diaphragm

More Related