15oicpp
                     AN INTRODUCTION TO
CARBOXYLIC ACIDS 
AND THEIR DERIVATIVES
  2015 
KNOCKHARDY PUBLISHING SPECIFICATIONS
KNOCKHARDY PUBLISHING
CARBOXYLIC ACIDS
INTRODUCTION
This Powerpoint show is one of several produced to help students 
understand selected topics at AS and A2 level Chemistry. It is based on the 
requirements of the AQA and OCR specifications but is suitable for other 
examination boards.
Individual students may use the material at home for revision purposes or it 
may be used for classroom teaching if an interactive white board is 
available.
Accompanying notes on this, and the full range of AS and A2 topics, are 
available from the KNOCKHARDY SCIENCE WEBSITE at...
www.knockhardy.org.uk/sci.htm
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CARBOXYLIC ACIDS
               CONTENTS
•  Structure of carboxylic acids   
•  Nomenclature
•  Physical properties of carboxylic acids
•  Preparation of carboxylic acids
•  Chemical properties of carboxylic acids
•  Acyl chlorides
•  Esters
•  Triglycerides and fats
•  Biofuels
  
CARBOXYLIC ACIDS
Before you start it would be helpful to…
•  Recall the definition of a covalent bond
•  Recall the difference types of physical bonding
•  Be able to balance simple equations
•  Be able to write out structures for simple organic molecules
•  Understand the IUPAC nomenclature rules for simple organic compounds
•  Recall the chemical properties of alkanes and alkenes  
  
STRUCTURE OF CARBOXYLIC ACIDS
•  contain the carboxyl functional group COOH
•  the bonds are in a planar arrangement
  
STRUCTURE OF CARBOXYLIC ACIDS
•  contain the carboxyl functional group COOH
•  the bonds are in a planar arrangement
•  include a carbonyl (C=O) group and
a hydroxyl (O-H) group
  
STRUCTURE OF CARBOXYLIC ACIDS
•  contain the carboxyl functional group COOH
•  the bonds are in a planar arrangement
•  include a carbonyl (C=O) group and
a hydroxyl (O-H) group
•  are isomeric with esters :- RCOOR’
  
HOMOLOGOUS SERIES
Carboxylic acids form a homologous series
     HCOOH  CH3COOH    C2H5COOH
  
HOMOLOGOUS SERIES
Carboxylic acids form a homologous series
     HCOOH  CH3COOH    C2H5COOH
        With more carbon atoms, there can be structural isomers 
C3H7COOH (CH3)2CHCOOH
  
INFRA-RED SPECTROSCOPY
IDENTIFYING CARBOXYLIC ACIDS USING INFRA RED SPECTROSCOPY
Differentiation Compound O-H  C=O
ALCOHOL YES   NO
CARBOXYLIC ACID YES  YES
ESTER  NO  YES
            ALCOHOL       CARBOXYLIC ACID     ESTER
         O-H absorption      O-H + C=O absorption             C=O absorption
  
NAMING CARBOXYLIC ACIDS
Acids are named according to standard IUPAC rules
•  select the longest chain of C atoms containing the COOH group;  
•  remove the e and add oic acid after the basic name
•  number the chain starting from the end nearer the COOH group
•  as in alkanes, prefix with alkyl substituents
•  side chain positions are based on the C in COOH being 1
   e.g.    CH3 - CH(CH3) - CH2 - CH2 - COOH    is called  4-methylpentanoic acid
  
NAMING CARBOXYLIC ACIDS
Acids are named according to standard IUPAC rules
•  select the longest chain of C atoms containing the COOH group;  
•  remove the e and add oic acid after the basic name
•  number the chain starting from the end nearer the COOH group
•  as in alkanes, prefix with alkyl substituents
•  side chain positions are based on the C in COOH being 1
 METHANOIC ACID ETHANOIC ACID    PROPANOIC ACID
  
NAMING CARBOXYLIC ACIDS
Acids are named according to standard IUPAC rules
•  select the longest chain of C atoms containing the COOH group;  
•  remove the e and add oic acid after the basic name
•  number the chain starting from the end nearer the COOH group
•  as in alkanes, prefix with alkyl substituents
•  side chain positions are based on the C in COOH being 1
BUTANOIC ACID 2-METHYLPROPANOIC ACID
  
NAMING CARBOXYLIC ACIDS
Acids are named according to standard IUPAC rules 
Many carboxylic acids are still known under their trivial names, some 
having been called after characteristic properties or their origin.
Formula Systematic name (trivial name) origin of name
HCOOH        methanoic acid  formic acid latin for ant
CH3COOH   ethanoic acid  acetic acid latin for vinegar
C6H5COOH     benzenecarboxylic acid benzoic acid from benzene
  
PHYSICAL PROPERTIES
BOILING POINT
Increases as size increases  -  higher induced dipole-dipole interactions
     101°C     118°C           141°C        164°C
  
PHYSICAL PROPERTIES
BOILING POINT
Increases as size increases  -  higher induced dipole-dipole interactions
     101°C     118°C           141°C        164°C
Boiling point is higher for “straight” chain isomers.
164°C 154°C
Greater branching  =  lower inter-molecular forces = lower boiling point
  
PHYSICAL PROPERTIES
BOILING POINT
Increases as size increases  -  higher induced dipole-dipole interactions
Carboxylic acids have high boiling points for their relative mass
The effect of hydrogen bonding on the boiling point of compounds of similar mass
Compound Formula Mr b. pt. (°C) Comments
ethanoic acid CH3COOH 60    118               + h-bonding
propan-1-ol C3H7OH 60     97     + h-bonding
propanal C2H5CHO 58     49     + permanent dipole-dipole
butane C4H10 58  - 0.5        induced dipole-dipole
  
PHYSICAL PROPERTIES
BOILING POINT
Increases as size increases  -  higher induced dipole-dipole interactions
Carboxylic acids have high boiling points for their relative mass
•  arises from inter-molecular hydrogen bonding due to polar O—H bonds
HYDROGEN 
BONDING
            AN EXTREME CASE... DIMERISATION
•  extra inter-molecular attraction  =  more energy to separate molecules
  
PHYSICAL PROPERTIES
SOLUBILITY
•  carboxylic acids are soluble in organic solvents
•  they are also soluble in water due to hydrogen bonding
HYDROGEN 
BONDING
  
PHYSICAL PROPERTIES
SOLUBILITY
•  carboxylic acids are soluble in organic solvents
•  they are also soluble in water due to hydrogen bonding
HYDROGEN 
BONDING
•  small ones dissolve readily in cold water
•  as mass increases, the solubility decreases
•  benzoic acid is fairly insoluble in cold but soluble in hot water
  
PREPARATION OF CARBOXYLIC ACIDS
Oxidation of aldehydes RCHO    +    [O]      ——>     RCOOH
Hydrolysis of esters RCOOR  +  H2O                 RCOOH   +   ROH
Hydrolysis of acyl chlorides RCOCl   +    H2O    ——>    RCOOH   +   HCl
Hydrolysis of nitriles RCN    +    2 H2O    ——>    RCOOH   +   NH3
Hydrolysis of amides RCONH2  +   H2O   ——>    RCOOH   +   NH3
  
CHEMICAL PROPERTIES
ACIDITY
weak acids RCOOH  +   H2O(l)               RCOO¯(aq)    +   H O+3 (aq)
form salts RCOOH   +   NaOH(aq)   ——>   RCOO¯Na+(aq)   +   H2O(l)
2RCOOH   +   Mg(s)   ——>   (RCOO¯) 2+2Mg (aq)   +   H2(g)
  
CHEMICAL PROPERTIES
ACIDITY
weak acids RCOOH  +   H2O(l)               RCOO¯(aq)    +   H +3O (aq)
form salts RCOOH   +   NaOH(aq)   ——>   RCOO¯Na+(aq)   +   H2O(l)
2RCOOH   +   Mg(s)   ——>   (RCOO¯)2Mg2+(aq)   +   H2(g)
The acid can be liberated from its salt by treatment with a stronger acid.
e.g. RCOO¯ Na+(aq)    +    HCl(aq)   ——>    RCOOH   +   NaCl(aq)
Conversion of an acid to its water soluble salt followed by acidification of 
the salt to restore the acid is often used to separate acids from a mixture.
  
CHEMICAL PROPERTIES
ACIDITY
weak acids RCOOH  +   H2O(l)               RCOO¯(aq)    +   H +3O (aq)
form salts RCOOH   +   NaOH(aq)   ——>   RCOO¯Na+(aq)   +   H2O(l)
2RCOOH   +   Mg(s)   ——>   (RCOO¯) Mg2+2 (aq)   +   H2(g)
The acid can be liberated from its salt by treatment with a stronger acid.
e.g. RCOO¯ Na+(aq)    +    HCl(aq)   ——>    RCOOH   +   NaCl(aq)
Conversion of an acid to its water soluble salt followed by acidification of 
the salt to restore the acid is often used to separate acids from a mixture.
QUALITATIVE ANALYSIS
Carboxylic acids are strong enough acids to liberate CO2 from carbonates
Phenols are also acidic but not are not strong enough to liberate CO2.
  
ESTERIFICATION
Reagent(s) alcohol + strong acid catalyst   (e.g. conc. H2SO4 )
Conditions reflux
Product ester
Equation     e.g. CH3CH2OH(l)  +  CH3COOH(l)     CH3COOC2H5(l)  +   H2O(l)
  ethanol           ethanoic acid    ethyl ethanoate
  
ESTERIFICATION
Reagent(s) alcohol + strong acid catalyst   (e.g. conc. H2SO4 )
Conditions reflux
Product ester
Equation     e.g. CH3CH2OH(l)  +  CH3COOH(l)     CH3COOC2H5(l)  +   H2O(l)
  ethanol           ethanoic acid    ethyl ethanoate
Notes Conc. H2SO4 is a dehydrating agent  -  it removes water
causing the equilibrium to move to the right and thus
increases the yield of the ester
  
ESTERIFICATION
Reagent(s) alcohol + strong acid catalyst   (e.g conc. H2SO4 )
Conditions reflux
Product ester
Equation     e.g. CH3CH2OH(l)  +  CH3COOH(l)     CH3COOC2H5(l)  +   H2O(l)
  ethanol           ethanoic acid    ethyl ethanoate
Notes Conc. H2SO4 is a dehydrating agent  -  it removes water
causing the equilibrium to move to the right and thus
increases the yield of the ester
Naming esters Named from the original  alcohol and carboxylic acid
      CH3OH   +  CH3COOH             CH3COOCH3   +   H2O
from ethanoic acid        CH3COOCH3     from methanol
                  METHYL ETHANOATE
  
CHLORINATION OF CARBOXYLIC ACIDS
Chlorination involves replacing the OH with a Cl 
Product acyl chloride
Reagent thionyl chloride  SOCl2
Conditions DRY conditions
Equation CH3COOH    +    SOCl2    ——>   CH3COCl   +    SO2   +    HCl
Alternative
method CH3COOH   +   PCl5    ——>    CH3COCl   +    POCl3   +    HCl
phosphorus(V) chloride
  
ACYL CHLORIDES
Structure  Replace the OH of a carboxylic acid with a Cl atom
 ETHANOYL CHLORIDE
 
Nomenclature Named from corresponding acid
… remove   -ic     add   -yl chloride
CH3COCl      ethanoyl (acetyl) chloride
C6H5COCl     benzene carbonyl (benzoyl) chloride
 
  
ACYL CHLORIDES - PROPERTIES
Physical •  polar, colourless liquids which fume in moist air



  
ACYL CHLORIDES - PROPERTIES
Physical •  polar, colourless liquids which fume in moist air



Chemical •  attacked at the positive carbon centre by nucleophiles
   such as water, alcohols, ammonia and amines
•  undergo addition-elimination reactions
•  MUCH MORE REACTIVE THAN…
   CARBOXYLIC ACIDS AND ACID ANHYDRIDES
  
ACYL CHLORIDES - REACTIONS
WATER
Product(s) carboxylic acid + HCl (fume in moist air / strong
  acidic solution formed)
Conditions cold water
Equation CH3COCl(l)    +   H2O(l)   —>    CH3COOH(aq)   + HCl(aq)
Mechanism addition-elimination
  
ACYL CHLORIDES - REACTIONS
WATER
Product(s) carboxylic acid + HCl (fume in moist air /
  strong acidic solution formed)
Conditions cold water
Equation CH3COCl(l)    +   H2O(l)   —>    CH3COOH(aq)   + HCl(aq)
Mechanism addition-elimination
ALCOHOLS
Product(s) ester + hydrogen chloride
Conditions reflux in dry (anhydrous) conditions 
Equation CH3COCl(l)   +   CH3OH(l)    —>    CH3COOCH3(l)  +  HCl(g)
Mechanism addition-elimination
  
ACYL CHLORIDES - REACTIONS
AMMONIA
Product(s) Amide + hydrogen chloride
Conditions Low temperature and excess ammonia. Vigorous reaction.
Equation CH3COCl(l)    +   NH3(aq)     —>    CH3CONH2(s)    +    HCl(g)
            or CH3COCl(l)   +   2NH3(aq)    —>    CH3CONH2(s)    +    NH4Cl(s)
Mechanism addition-elimination
  
ACYL CHLORIDES - REACTIONS
AMMONIA
Product(s) Amide + hydrogen chloride
Conditions Low temperature and excess ammonia. Vigorous reaction.
Equation CH3COCl(l)    +   NH3(aq)     —>    CH3CONH2(s)    +    HCl(g)
            or CH3COCl(l)   +   2NH3(aq)    —>    CH3CONH2(s)    +    NH4Cl(s)
Mechanism addition-elimination
AMINES
Product(s) N-substituted amide + hydrogen chloride
Conditions anhydrous
Equation CH3COCl(l)  +  C2H5NH2(aq)   —>  CH3CONHC2H5(s)  + HCl(g)
         or   CH3COCl(l) +  2C2H5NH2(aq)  —>  CH3CONHC2H5(l)  +  C2H5NH3Cl(s)
Mechanism addition-elimination
  
ESTERS
Structure Substitute an organic group for the H in carboxylic acids
Nomenclature first part from alcohol, second part from acid
e.g.     methyl ethanoate  CH3COOCH3
 METHYL ETHANOATE  ETHYL METHANOATE
  
ESTERS
Structure Substitute an organic group for the H in carboxylic acids
Nomenclature first part from alcohol, second part from acid
e.g.     methyl ethanoate  CH3COOCH3
 METHYL ETHANOATE  ETHYL METHANOATE
Preparation From carboxylic acids, acyl chlorides and acid anhydrides
Reactivity Unreactive compared with acids and acyl chlorides
  
ESTERS
Structure Substitute an organic group for the H in carboxylic acids
Nomenclature first part from alcohol, second part from acid
e.g.     methyl ethanoate  CH3COOCH3
 METHYL ETHANOATE  ETHYL METHANOATE
Preparation From carboxylic acids, acyl chlorides and acid anhydrides
Reactivity Unreactive compared with acids and acyl chlorides
Isomerism Esters are structural isomers of carboxylic acids
  
STRUCTURAL ISOMERISM – FUNCTIONAL GROUP
Classification    CARBOXYLIC ACID                 ESTER
Functional Group             R-COOH                R-COOR
Name     PROPANOIC ACID      METHYL ETHANOATE
Physical properties O-H bond gives rise       No hydrogen bonding
to hydrogen bonding;       insoluble in water
get higher boiling point
and solubility in water
Chemical properties acidic       fairly unreactive
react with alcohols       hydrolysed to acids
  
PREPARATION OF ESTERS - 1
Reagent(s) alcohol  +  carboxylic acid
Conditions reflux with a strong acid catalyst  (e.g.  conc. H2SO4 )
Equation    e.g. CH3CH2OH(l)  +  CH3COOH(l)     CH3COOC2H5(l)  +   H2O(l)
  ethanol           ethanoic acid    ethyl ethanoate
Notes Conc. H2SO4 is a dehydrating agent  -  it removes water
causing the equilibrium to move to the right and thus
increases the yield of the ester
    For more details see under ‘Reactions of carboxylic acids’
  
PREPARATION OF ESTERS - 2
Reagent(s) alcohol  +  acyl chloride
Conditions reflux under dry conditons
Equation    e.g.  CH3OH(l)  +   CH3COCl(l)   ——>   CH3COOCH3(l)  +   HCl(g)
 methanol        ethanoyl                  methyl                
           chloride               ethanoate
Notes Acyl chlorides are very reactive
but must be kept dry as they react
with water.
  
PREPARATION OF ESTERS - 3
Reagent(s) alcohol  +  acid anhydride
Conditions reflux under dry conditons
Equation    e.g.  CH3OH(l)   +   (CH3CO)2O(l)   ——>  CH3COOCH3(l) +  CH3COOH(l)
             methanol        ethanoic                   methyl                 ethanoic
       anhydride  ethanoate       acid
Notes Acid anhydrides are not as reactive as
acyl chlorides so the the reaction is slower.
The reaction is safer - it is less exothermic.
Acid anhydrides are less toxic.
  
HYDROLYSIS OF ESTERS
Hydrolysis is the opposite of esterification
     ESTER  +  WATER      CARBOXYLIC ACID  +  ALCOHOL
  HCOOH        +       C2H5OH
METHANOIC     ETHANOL
     ACID
 ETHYL METHANOATE
  
HYDROLYSIS OF ESTERS
Hydrolysis is the opposite of esterification
     ESTER  +  WATER      CARBOXYLIC ACID  +  ALCOHOL
  HCOOH        +       C2H5OH
METHANOIC     ETHANOL
     ACID
 ETHYL METHANOATE
 METHYL ETHANOATE
  
HYDROLYSIS OF ESTERS
Hydrolysis is the opposite of esterification
     ESTER  +  WATER      CARBOXYLIC ACID  +  ALCOHOL
  HCOOH        +       C2H5OH
METHANOIC     ETHANOL
     ACID
 ETHYL METHANOATE
CH3COOH      +       CH3OH
ETHANOIC  METHANOL
     ACID
 METHYL ETHANOATE
  
HYDROLYSIS OF ESTERS
Hydrolysis is the opposite of esterification
     ESTER  +  WATER      CARBOXYLIC ACID  +  ALCOHOL
The products of hydrolysis depend on the conditions used...
acidic         CH3COOCH3    +   H2O  CH3COOH    +    CH3OH
alkaline         CH3COOCH3   +  NaOH    ——>   CH3COO¯ Na+   +   CH3OH
  
HYDROLYSIS OF ESTERS
Hydrolysis is the opposite of esterification
     ESTER  +  WATER      CARBOXYLIC ACID  +  ALCOHOL
The products of hydrolysis depend on the conditions used...
acidic         CH3COOCH3    +   H2O  CH3COOH    +    CH3OH
alkaline         CH3COOCH3   +  NaOH    ——>   CH3COO¯ Na+   +   CH3OH
  
HYDROLYSIS OF ESTERS
Hydrolysis is the opposite of esterification
     ESTER  +  WATER      CARBOXYLIC ACID  +  ALCOHOL
The products of hydrolysis depend on the conditions used...
acidic         CH3COOCH3    +   H2O  CH3COOH    +    CH3OH
alkaline         CH3COOCH3   +  NaOH    ——>   CH3COO¯ Na+   +   CH3OH
        If the hydrolysis takes place under alkaline conditions,
        the organic product is a water soluble ionic salt
  
HYDROLYSIS OF ESTERS
Hydrolysis is the opposite of esterification
     ESTER  +  WATER      CARBOXYLIC ACID  +  ALCOHOL
The products of hydrolysis depend on the conditions used...
acidic         CH3COOCH3    +   H2O  CH3COOH    +    CH3OH
alkaline         CH3COOCH3   +  NaOH    ——>   CH3COO¯ Na+   +   CH3OH
        If the hydrolysis takes place under alkaline conditions,
        the organic product is a water soluble ionic salt
        The carboxylic acid can be made by treating the salt with HCl
        CH3COO¯ Na+   +    HCl     ——>    CH3COOH    +    NaCl 
  
USES OF ESTERS
Despite being fairly chemically unreactive, esters are useful as ...
•  flavourings apple 2-methylbutanoate
pear 3-methylbutylethanoate
banana 1-methylbutylethanoate
pineapple butylbutanoate
rum 2-methylpropylpropanoate
•  solvents nail varnish remover  - ethyl ethanoate
•  plasticisers 
  
TRIGLYCERIDES AND FATS
Triglycerides
•  are the most common component of edible fats and oils
•  are triesters of the alcohol glycerol, (propane-1,2,3-triol) and fatty acids
a triglyceride glycerol
  
TRIGLYCERIDES AND FATS
Triglycerides
•  are the most common component of edible fats and oils
•  are triesters of the alcohol glycerol, (propane-1,2,3-triol) and fatty acids
Saponification
•  alkaline hydrolysis of triglycerol esters produces soaps
•  a simple soap is the salt of a fatty acid
•  as most oils contain a mixture of triglycerols, soaps are not compounds
•  the quality of a soap depends on the oils from which it is made
  
FATTY ACIDS
Carboxylic acids that are obtained from natural oils and fats; they can be…
Saturated CH3(CH2)16COOH               octadecanoic acid
    (stearic acid)
                    
  
FATTY ACIDS
Carboxylic acids that are obtained from natural oils and fats; they can be…
Saturated CH3(CH2)16COOH               octadecanoic acid
    (stearic acid)
                    9
Unsaturated CH3(CH2)7CH=CH(CH2)7COOH octadec-9-enoic acid  
     (oleic acid)
cis (Z) isomer
trans (E) isomer
                 
          
  
FATTY ACIDS
Carboxylic acids that are obtained from natural oils and fats; they can be…
Saturated CH3(CH2)16COOH               octadecanoic acid
    (stearic acid)
                    9
Unsaturated CH3(CH2)7CH=CH(CH2)7COOH octadec-9-enoic acid  
     (oleic acid)
cis (Z) isomer
trans (E) isomer
                 
            12  9
CH3(CH2)4CH=CHCH2CH=CH(CH2)7COOH
 octadec-9,12-dienoic  acid   (linoleic acid)
FATTY ACIDS AND HEALTH
Saturated •  solids at room temperature
•  found in meat and dairy products
•  are bad for health
•  increase cholesterol levels - can lead to heart problems
  
  
FATTY ACIDS AND HEALTH
Saturated •  solids at room temperature
•  found in meat and dairy products
•  are bad for health
•  increase cholesterol levels - can lead to heart problems
  
Mono
unsaturated •  contain just one C=C
•  thought to be neutral to our health
•  found in olives, olive oil, groundnut oil, nuts, avocados
  
FATTY ACIDS AND HEALTH
Saturated •  solids at room temperature
•  found in meat and dairy products
•  are bad for health
•  increase cholesterol levels - can lead to heart problems
  
Mono
unsaturated •  contain just one C=C
•  thought to be neutral to our health
•  found in olives, olive oil, groundnut oil, nuts, avocados
Poly
unsaturated •  are considered to be ‘good fats’
•  contain more than one C=C bond
•  tend to be liquids at room temperature, eg olive oil. 
•  can be split into two main types...
Omega 3 - fatty acids
Omega 6 - fatty acids
  
FATTY ACIDS AND HEALTH
Saturated •  solids at room temperature
•  found in meat and dairy products
•  are bad for health
•  increase cholesterol levels - can lead to heart problems
  
Mono
unsaturated •  contain just one C=C
•  thought to be neutral to our health
•  found in olives, olive oil, groundnut oil, nuts, avocados
Poly
unsaturated •  are considered to be ‘good fats’
•  contain more than one C=C bond
•  tend to be liquids at room temperature, eg olive oil. 
•  can be split into two main types...
Omega 3 - fatty acids
Omega 6 - fatty acids
  
OMEGA 3 and 6 FATTY ACIDS
Omega 3 - fatty acids lower the total amount of fat in the blood
and can lower blood pressure and decrease
the risk of cardiovascular disease
                     3           
 (omega) end CH3CH2CH=CHCH2CH2CH2CH2CH=CH(CH2)7COOH
The omega numbering system starts from the 
opposite end to the carboxylic acid group
  
OMEGA 3 and 6 FATTY ACIDS
Omega 3 - fatty acids lower the total amount of fat in the blood
and can lower blood pressure and decrease
the risk of cardiovascular disease
                     3           
 (omega) end CH3CH2CH=CHCH2CH2CH2CH2CH=CH(CH2)7COOH
Omega 6 - fatty acids reduce the risk of cardiovascular disease but 
can contribute to allergies and inflammation
                       
          6
 (omega) end CH3CH2CH2CH2CH2CH=CHCH2CH=CH(CH2)7COOH
  
CHOLESTEROL
•  a fatty substance which is found in the blood
•  it is mainly made in the body
•  plays an essential role in how every cell in the body works
•  eating too much saturated fat increases cholesterol levels
•  too much cholesterol in the blood can increase the risk of heart problems
  
CHOLESTEROL
•  a fatty substance which is found in the blood
•  it is mainly made in the body
•  plays an essential role in how every cell in the body works
•  eating too much saturated fat increases cholesterol levels
•  too much cholesterol in the blood can increase the risk of heart problems
Ways to reduce cholesterol levels
•  cut down on saturated fats and trans fats
   (trans fats are more stable and difficult to break down in the body)
•  replace them with monounsaturated fats and polyunsaturated fats
•  eat oily fish
•  have a high fibre diet;  porridge, beans, fruit and vegetables
•  exercise regularly
  
BIOFUELS
What are they?
Liquid fuels made from plant material and recycled elements of the food chain
Biodiesel
An alternative fuel which can be made from waste vegetable oil or from oil 
produced from seeds. It can be used in any diesel engine, either neat or 
mixed with petroleum diesel. 
vegetable oil glycerol biodiesel
It is a green fuel, does not contribute to the carbon dioxide (CO2) burden and 
produces drastically reduced engine emissions. It is non-toxic and 
biodegradable.
  
BIOFUELS
Advantages •  renewable - derived from sugar beet, rape seed
•  dramatically reduces emissions
•  carbon neutral
•  biodegradable
•  non-toxic
•  fuel & exhaust emissions are less unpleasant
•  can be used directly in unmodified diesel engine
•  high flashpoint - safer to store & transport
•  simple to make
•  used neat or blended in any ratio with petroleum diesel
 
  
BIOFUELS
Advantages •  renewable - derived from sugar beet, rape seed
•  dramatically reduces emissions
•  carbon neutral
•  biodegradable
•  non-toxic
•  fuel & exhaust emissions are less unpleasant
•  can be used directly in unmodified diesel engine
•  high flashpoint - safer to store & transport
•  simple to make
•  used neat or blended in any ratio with petroleum diesel
 
Disadvantages •  poor availability - very few outlets & manufacturers
•  more expensive to produce
•  poorly made biodiesel can cause engine problems
  
BIOFUELS
Advantages •  renewable - derived from sugar beet, rape seed
•  dramatically reduces emissions
•  carbon neutral
•  biodegradable
•  non-toxic
•  fuel & exhaust emissions are less unpleasant
•  can be used directly in unmodified diesel engine
•  high flashpoint - safer to store & transport
•  simple to make
•  used neat or blended in any ratio with petroleum diesel
 
Disadvantages •  poor availability - very few outlets & manufacturers
•  more expensive to produce
•  poorly made biodiesel can cause engine problems
Future
problems •  there isn’t enough food waste to produce large amounts
•  crops grown for biodiesel use land for food crops
•  a suitable climate is needed to grow most crops
•  some countries have limited water resources
  
AN INTRODUCTION TO
CARBOXYLIC ACIDS 
AND THEIR DERIVATIVES
THE END
  
© 2015 JONATHAN HOPTON & KNOCKHARDY PUBLISHING