info@ormalearn.com   +254721524786

Answers section


Related Topic: Organic Chemistry 1

Related Subtopic: Extraction of nitrogen from air



Questions 4.1

  1. First, we need a Chamber, A, to set air flowing continuously from the atmosphere into Chamber B and further into the distillation column. Name the device, Chamber A.
  2. Atmospheric air contains dust, water vapour, and carbon (IV) oxide which must be removed. How can dust be removed? Suggest a name for Chamber B.
  3. When compressed and cooled a little below room temperature, water vapour readily condenses, while carbon (IV) oxide turns to solid (undergoes deposition) at -78.5 oC on further cooling. (a) What is the function of Chamber C? (b) Name the substances tapped from Chamber C and D respectively. (c) Suggest one use of the by-product obtained from Chamber D.
  4. Explain why, although sodium hydroxide solution absorbs carbon (IV) oxide gas, it is not suitable for removing the gas in this process.
  5. Name the process that takes place in Chamber E.
  6. During distillation, liquid air is allowed to evaporate and distill as fractions. Identify one way in which this process is (a) similar to distillation of crude oil (b) differs from the distillation of crude oil.
  7. Suggest a reason why air should be liquefied before its components are separated.
  8. An air distillation plant is considered as an economical and profitable investment. Suggest two reasons for this.


Answers to Questions 4.1


  1. Pump
  2. Dust is removed by filtration or dust precipitation. Chamber B is air filter or dust precipitator.
  3. (a) Chamber C removes water vapor by cooling and condensing it into liquid. (b) Liquid water and solid carbon (IV) oxide are obtained from Chamber C and D respectively (c) The by-product is used as a freezer or coolant.
  4. Very large quantities of sodium hydroxide would be required for the industrial process, making it uneconomical.
  5. Condensation (of the remaining components of air into liquid air).
  6. (a) The use of fractionating column. (b) This process involves cooling and condensation while crude oil involves external heating. Components with higher boiling points condense higher up in the column, unlike in crude oil distillation.
  7. It is liquefied so that fractional distillation can be applied. There is no other known physical means of separating gases directly (in their natural state).
  8. It has many useful by-products with important industrial applications.