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Form 3 Chemistry: Organic Chemistry I Video Questions and Answers

Form 3 Chemistry: Organic Chemistry I Video Topical Questions and Answers.
In this session, we are going to solve several questions in organic chemistry I, which is a Form 3 chemistry topic.

Lessons (37)

• 1.    A solution of chlorine is tetrachloromethane turns colourless when propene gas is bubbled through it. (a) What type of reaction takes place. (b) Write an equation for the reaction above.
  4m 31s

• 2.    a) The table below gives information about the major constituents of crude oil. Study it and answer the questions that follow. (i) Which one of the constituents of crude oil has molecules with the highest number of carbon atoms. Explain (ii) Name the process you would use to separate a mixture of petrol and diesel and explain how the separation takes place
  10m 21s

• 3.    The reaction of propane with chlorine gas gave a compound of formula #C_3H_7Cl.# (a) What condition is necessary for the above reaction to take place?(b) Draw two structural formulae of the compound, #C_3H_7Cl#
  4m 52s

• 4.    Methane reacts with oxygen as shown by the equations I and II below (I) #CH_4#(g) + #2O_2#(g)--->#CO_2#(g)+#2H_2O#(l) (II) #2CH_4(g)#+#3O_2(g)#---->2CO(g)+#4H_2O(l)# Which one of the two reactions represents the complete combustion of methane? Explain.
  1m 22s

• 5.    Complete the table below by inserting the missing information in the space provided
  3m 22s

• 6.    The empirical formula of a hydrocarbon is #C_2H_3#. The hydrocarbon has a relative molecular mass of 54. (H=1.0, C=12.0). (a) Determine the molecular formula of the hydrocarbon. (b) Draw the structural formula of the hydrocarbon (c) To which homologous series does the hydrocarbon drawn in (b) above belong?
  4m 46s

• 7.    Name and draw the structure of the compound formed when methane reacts with excess chlorine in the presence of U.V light.
  3m 40s

• 8.    The formula given below represents a portion of a polymer. Give: (a)the name of the polymer (b)one disadvantage of continued use of this polymer.
  1m 24s

• 9.    A hydrocarbon slowly decolorizes bromine gas in the presence of sunlight but does not decolorize acidified potassium manganate(VII). Name and draw the structural formula of the fourth member of the series to which the hydrocarbon belongs.
  2m 38s

• 10.    Compound L reacts with hydrogen bromine gas to give another compound whose structure is: (a) Give the structural formula and name of compound L (b) Write an equation for the reaction which take place between ethyne and excess chlorine gas.
  7m 15s

• 11.    One of the fuels associated with crude oil is natural gas. Name the main constituent of natural gas and write an equation for its complete combustion.
  2m 1s

• 12.    Bromine reacts with ethane as shown below: #C_2H_6# + #Br_2# ?#C_2H_5Br#+HBr (a) What condition is necessary for this reaction to occur? (b) Identify the bonds which are broken and those that are formed.
  3m 18s

• 13.    A hydrocarbon P was found to decolourise bromine water. On complete combustion of 2 moles of P, 6 moles of carbon(iv)oxide and 6 moles of water were formed. (a) Write the structural formula of P (b) Give the name of P (c) Name one industrial source of P
  6m 37s

• 14.    In the presence of U.V light, ethane gas undergoes substitution reaction with chlorine. (a) What is meant by the term: substitution reaction? (b) Give the structural formula and the name of the organic product formed when equal volumes of ethane and chlorine react together.
  1m 54s

• 15.    But-2-ene undergoes hydrogenation according to the equation given below: #CH_3CH#=#CHCH_3#(g)+#H_2#(g)---->#CH_3CH_2CH_2CH_3#(g) (a) Name the product formed when but-2-ene reacts with hydrogen gas. (b) State one industrial use of hydrogenation
  1m 22s

• 16.    (a) State the observation made when excess pentene is reacted with bromine gas. (b) Name the compound formed in (a) above.
  4m 16s

• 17.    (a) What is the name given to the smallest repeating unit of a polymer? (b) Draw the structure of the smallest repeating unit of a polyvinyl chloride.
  1m 43s

• 18.    Name the organic compound formed when #CH_3CH_2CH_2CH_2OH# is reacted with concentrated sulphuric acid(VI) acid at #170^0C#.
  2m 23s

• 19.    (a) Crude oil is a source of many compounds that contain carbon and hydrogen only. (i) Name the process used to separate the components of crude oil. (ii) On what two physical properties of the above components does the separation depend? (b) Under certain conditions, hexane can be converted to two products. The formula of one of the products is #C_3H_8#.
  0m 0s

• 20.    Give the name and draw the structural formula of the compound formed when one mole of ethyne reacts with one mole of chlorine gas.
  5m 54s

• 21.    Study the flow chart below and answer the questions that follow (a)Identify N and P. (b)What name is given to the type of halogenation/chlorination reaction in step 2?
  6m 11s

• 22.    (a)What is meant by isomerism? (b) Draw and name two isomers of butane.
  6m 21s

• 23.    A group of compounds called chlorofluorocarbons have a wide range of uses but they also have harmful effects on the environment. State one: (a)use of chlorofluorocarbons (b)harmful effect of chlorofluorocarbons on the environments.
  2m 11s

• 24.    The relative formula mass of a hydrocarbon is 58. Draw and name two possible structures of hydrocarbon (C=12.0;H=1.0).
  5m 10s

• 25.    (a)Draw and name the structure of the compound formed when one mole of ethyne reacts with one mole of hydrogen bromide. (b)Draw the structures of the alkynes whose molecular formula is #C_4H_6#
  7m 7s

• 26.    The figure below represents the set up that was used to crack an alkaline. (a)What was the purpose of the sand? (b)After some time, a colourless gas G is collected in the test-tube. Describe a chemical test and the observations that would be made in order to identify the class of compounds to which gas G belongs
  3m 40s

• 27.    Draw the structures and give the names of three alkenes having molecular formula #C_5H_10#.
  6m 49s

• 28.    Exhaust fumes of some cars contain carbon (II) oxide and other gases. (a)Explain how carbon (II) oxide is formed in the internal combustion engines. (b)Name two gases other than carbon (II) oxide that are contained in the exhaust fumes and are pollutants.
  2m 19s

• 29.    Draw and name the isomers of pentane
  5m 59s

• 30.    Study the flow chart below and answer the questions that follow: (a)Identify: (i) X (ii) Y (b)State two uses of polyvinylchloride.
  4m 46s

• 31.    (a)Draw and name the isomers of butyne. (b)State one use of polystyrene.
  5m 27s

• 32.    (a)State one source of alkanes. (b)Ethane gas was reacted with 1 mole of bromine gas. State one observation made during this reaction
  2m 12s

• 33.    Draw and name the isomers of pentane.
  6m 42s

• 34.    The set-up in the figure below was used to prepare a sample of ethane gas. Study it and answer the questions that follow. (a)Name B. (b)Write an equation for the complete combustion of ethane. (c)State one use of ethane.
  5m 2s

• 35.    When ethene gas is compressed at a high temperature, a solid is formed. (a)Give the name of the solid. (b)Explain why it is not advisable to allow the solid to accumulate in the environment.
  3m 12s

• 36.    A monomer has the following structure. (a) Draw the structure of its polymer that contains three monomers (b) A sample of the polymer formed from the monomer has a molecular mass of 4992. Determine the number of monomers that formed the polymer (C=12;H=1.0)
  6m 55s

• 37.    Ethene is prepared in the laboratory by dehydration of ethanol. (a)Name a suitable dehydrating agent used in this process. (b)State the condition necessary for the reaction to occur. (c)Write an equation for the dehydration process.
  4m 29s