Fichas
Unit 2: Section 4: More Organic Chemistry
Fichas del conjunto (27)
- 1What is the type of mechanism and conditions for alkane → haloalkane?-Free-radical substitution
-UV light - 2What are the 3 stages to free-radical substitution?1. Initiation
2. Propagation
3. Termination - 3What happens during initiation?-Free radicals are produced.
Cl₂ → 2Cl● - 4What happens during propagation?-Free radicals are used up and created in a chain reaction.
Cl● +CH₄ → ●CH₃ +HCl
●CH₃ +Cl₂ → CH₃Cl + Cl● - 5What happens during termination?-Free radicals are mopped up.
Cl● + Cl● → Cl₂
●CH₃ + ●CH₃ → C₂H₆
●CH₃ + Cl● → CH₃Cl - 6What are CFCs?Chlorofluorocarbons
- 7What are chloroalkanes and chlorofluroalkanes used as?Solvents
- 8How is the ozone layer formed?O₂ + hv (UV radiation) → O● + O●
O₂ + O● → O₃ - 9How are chlorine free radicals formed?When the C-Cl bonds in CFCs are broken down by ultraviolet radiation.
- 10How do the chlorine free radicals attack the ozone layer?Cl● + O₃ → O₂ + ClO●
ClO● + O₃ → 2O₂ + Cl●
Overall: 2O₃ → 3O₂ - 11What is an alternative to CFCs?HFCs (hydrofluorocarbons)
- 12What is the type of mechanism and conditions for haloalkane → alcohol?-Nucleophillic substitution
-Warm aqueous sodium hydroxide - 13What is the type of mechanism and conditions for haloalkane → amine?-Nucleophilic substitution
-Ethanol
-Excess ammonia - 14What is the type of mechanism and conditions for haloalkane → nitrile?-Nucleophilic substitution
-Alcoholic potassium cyanide
-Reflux - 15What is the type of mechanism and conditions for haloalkane → alkene?-Elimination
-Ethanol
-Reflux - 16What does the OH(-) act as in different conditions?Aqueous conditions: nucleophile
Anhydrous conditions: base - 17What is the test for double bonds?-Bromine water
-Turns colourless if double bonds are present. - 18What is the type of mechanism and conditions for alkene → dibromoalkane?-Electrophilic addition
-Br₂ - 19What is the type of mechanism and conditions for alkene → haloalkane?-Electrophilic addition
-HBr - 20What conditions are required for the hydration of alkene → alcohol?-Steam
-300°C
-60 atm
-Phosphoric acid catalyst - 21What are the advantages of hydration of ethene?-Very fast
-Pure product
-Low labour costs - 22What are the disadvantages of hydration of ethene?-Ethene is from oil, a finite resource
-Continuous process so requires expensive equipment - 23What are the advantages of fermentation?-Uses sugars, a renewable resource
-Cheap equipment needed - 24What are the disadvantages of fermentation?-Very slow
-Very impure so requires further processing
-High labour costs - 25What conditions are needed for the dehydration of alcohol → alkene?-Reflux
-Ethanol
-Conc. sulfuric acid - 26What is the test for 1°, 2° and 3° alcohols?-Acidified potassium dichromate
1°- orange to green
2°- orange to green
3°- nvc - 27Which test is used for aldehydes and ketones?-Tollen's reagent
Aldehyde: silver mirror
Ketone: NVC