Alcohols And Halogenoalkanes Flashcards
What is a secondary alcohol?
To carbon atoms attached to the carbon that is joined to the hydroxide group
What is a tertiary alcohol?
Carbon attached to hydroxide group is attached to 3 other carbon atoms
What is a primary alcohol?
To hydrogen atoms attached to the carbon join to the hydroxide group
What is produced when alcohols are completely combusted?
Carbon dioxide
Water
What is the equation for when sodium reacts with ethanol?
2Na(s) + 2C(2)H(5)OH (l) –> 2CH3CH2O-,Na+ (alc) + H2 (g)
Sodium ethnocide (dissolved in ethanol)
What can the reaction between phosphorus five chloride and an alcohol be used as a test for?
Qualitative of test for the hydroxide group as hydrogen chloride gas is given off
What is the equation for the reaction between phosphorus chloride and ethanol?
C2H5OH + PCl5(s) –> C2H5Cl(l) + POCl3(l) + HCl
What is produced when a primary alcohol is oxidised?
An aldehyde which can be fully oxidised form a carboxylic acid
What is the colour change when a primary alcohol is a oxidised?
Orange to green
What can be used to oxidise alcohols?
Concentrated sulphuric acid
Na2Cr2O7
What is produced when a secondary alcohol is oxidised?
Ketone (propanone)
Double C=O bond in middle
What is produced when a tertiary alcohol is oxidised?
Not meant to be oxidised by common oxidising agents
What equipment must do use to oxidise a primary alcohol?
Reflux
Distillation
What equipment must be used to prepare a ketone from a secondary alcohol?
They have different boiling points which allows you to collect them as different samples
What is a primary halogenoalkane?
One carbon atom bonded to the carbon atom carrying the halogen
What is a secondary halogenoalkane?
To carbon atoms attached to the carbon atom with the halogen
What is a tertiary have halogenoalkane?
The carbon bonds it to the halogen attached are three other carbon atoms
How do you name halogenoalkanes?
DuPont
Rightmost digit: number of fluorine atom is per molecule
Tens digit: 1+ the number of hydrogen atoms
Hundred digit: number of carbon atoms -1
Thousands digit: number of double bonds in the molecule
Unaccounted for bonds occupied by chlorine atoms
Suffix of a B or C indicating unbalanced isomers
What sort of reaction is do halogenoalkanes generally undergo?
Substitution visit occasionally elimination
Flooring compounds are very stable say rarely undergo any reaction
What is the general equation for A hydrolysis reaction with a halogenoalkane?
The hydroxide group substitutes for the halogen
RX +H2O –> ROH + HX
RX + OH- –> ROH + X-
How do you speed up the hydrolysis reaction with a halogenoalkane?
The reaction with water is slow at room temperature but is more rapid with hydroxide ions
What is the order of reactivity of the halogenoalkanes? Why?
Chloroalkanes are less reactive than Bromoalkanes are Iodoalkanes as the C – CL bond is much stronger, showing strength is more important than electronegativity
What is alcoholic potassium hydroxide?
When potassium hydroxide is dissolved in ethanol
What sort of reaction occurs between alcoholic potassium hydroxide and a halogenoalkane?
Elimination
A molecule of hydrogen halide is eliminated from the molecule forming an alkane as a product
Give an sample of the reaction between an alcoholic potassium hydroxide and a halogen alkane
CH3BrCH3 + OH- –> CH2CH2 + H20 + Br-
How must be reaction between a halogen alkane and alcoholic potassium hydroxide be carried out?
Refluxed and heated
How alcoholic ammonia act when it reacts with a halogenoalkane?
Nucleophile due to the lone pair of electrons on the nitrogen atom, allowing them to easily replace a halogen atom
Under what conditions must reaction between a halogenoalkane and alcoholic ammonia be carried out?
With concentrated ammonia in ethanol in a sealed tube
If done in reflux the ammonia would it escape at the condenser as it doesn’t condense
Give an example of the reaction between alcoholic ammonia and a halogenoalkane
CH3I + NH3 –> CH3NH2(methylamine) + HI
Methylamine has a lone pair so reacts further
What does the result of the reaction between an alcoholic ammonia and a halogen alkane confirm?
The rate of hydrolysis of the halogens
1-chlorobutane
Describe an experiment that can be used to test the effect of the carbon skeleton in halogenoalkane
Three test tubes, containing either primary secondary or territory
Add 1 cm³ of silver nitrate
Add 1 cm³ of ethanol as a solvent
Leave them to stand after shaking
What are the results of the reaction testing the carbon skeleton on a halogenalkane?
Primary
How do you prepare a halogenoalkane from an alcohol?
With sodium bromide, water and concentrated sulphuric acid
Refluxed- sulphuric acid is added one drop at a time as the reaction is exothermic, the flask is also cooled using a beaker of cold water
Distilled- produces two layers and aqueous layer discarded
What is the equation for preparing a halogenoalkane from an alcohol?
NaBr + H2SO4 –> NaHSO4 + HBr
CH3CH2OH + HBr –> CH3CH2Br + H20
What properties are desirable in a refrigerant?
Not flammable, Not toxic, Unreactive, non-corrosive
(easily) compressible
does not harm the ozone layer
Boiling temperature below target temperature
high heat of vaporization high gas density
high critical temperature
How is the bonding in gaseous hydrogen halides best described?
Mainly covalent with an increasing tendency to wards ionic as you go up the group
Why is no chlorine produced when concentrated sulphuric in acid is added to solid sodium chloride yet bromine produced when added go sodium bromide?
The chlorine ion is a weaker reducing agent and the bromine ion
When extracting iodine from an aqueous a solution in a separating funnel, which layer is the hydrocarbon layer?
Top
What colour is chlorine water?
Pale yellow
What is the colour of the solution when chlorine water is added to potassium iodide solution?
Red/brown
