4. HYDROLYSIS
• The reaction of water with another chemical
compound to form two or more products,
involving ionization of the water molecule and
usually splitting the other compound.
• If a compound is represented by the formula AB in
which A and B are atoms or groups and water is
represented by the formula HOH, the hydrolysis
reaction may be represented by the
reversible chemical equation
AB + HOH ⇌ AH + BOH.
6. TYPES OF HYDROLYSIS
SALTS:
• This is the most common type of hydrolysis.
• Hydrolysis of salts generally refers to the reaction of
salt with water where it involves the interaction
between cations or anions of salts and water.
• During hydrolysis, a salt breaks down to form ions,
completely or partially depending upon the solubility
factor.
• Cations (positively-charged ions)
and anions (negatively-charged ions)
7. SALT HYDROLYSIS
• It is defined as the process in which a salt reacts with
water to give back the acid and base.
BA+HOH→HA+BOH
• It is considered as the reverse of neutralization.
• If the acid produced is strong and the base produced
is weak then cation reacts with water to give an acidic
solution. This is known as cationic hydrolysis.
• If the acid produced is weak and the base produced is
strong then anion reacts with water to give a basic
solution. This is known as anionic hydrolysis.
8. ACID AND BASE
• Acid–base-hydrolysis can be found during the
hydrolysis of esters or amides.
• Here, the process of hydrolysis occurs when
water or hydroxyl ion reacts with the carbon of
the carbonyl group of the ester or amide where
new compounds are formed.
• The products for both hydrolysis are
compounds with carboxylic acid groups.
9. ACIDIC HYDROLYSIS
• Acidic hydrolysis is simply the reverse
of esterification.
• The ester is heated with a large excess of
water containing a strong-acid catalyst.
• Like esterification, the reaction is reversible
and does not go to completion.
10. HYDROLYSIS OF AMIDES
• Amides are carboxylic acid derivatives where the –
OH of the carboxylic acid has been replaced by –
NH2, –NHR, or –NR2 of an amine. Since the
reaction between a carboxylic acid and an amine to
give an amide also liberates water
11. Adenosine Triphosphate (ATP)
• Most biochemical reactions that occur in living
organisms are in the form of ATP hydrolysis
which takes place with the help of enzymes
acting as catalysts.
• The catalytic action of enzymes allows the
hydrolysis or breaking down of proteins,
lipids, oils, fats and carbohydrates.
12. Adenosine Triphosphate (ATP)
• ATP hydrolysis is the
catabolic reaction process
by which chemical energy
that has been stored in the
high-energy
phosphoanhydride bonds
in adenosine triphosphate
is released by splitting
these bonds
13. HYDROGENATION
• Hydrogenation is a chemical reaction between
molecular hydrogen (H2) and another
compound or element, usually in the presence
of a catalyst.
• The process is commonly employed to reduce
or saturate organic compounds.
• Hydrogenation typically constitutes the
addition of pairs of hydrogen atoms to a
molecule, generally an alkene.
14. • Catalysts are required for the reaction to be
usable; non-catalytic hydrogenation takes place
only at very high temperatures.
• Hydrogenation reduces double and triple bonds
in hydrocarbons.
• Most hydrogenations use gaseous hydrogen
(H2), but some involve the alternative sources of
hydrogen, not H2: these processes are called
transfer hydrogenations.
15. Equipment used for hydrogenation
Today's bench chemist has three main choices of
hydrogenation equipment:
• Batch hydrogenation under atmospheric
conditions
• Batch hydrogenation at elevated temperature
and/or pressure
• Flow hydrogenation Batch
16. Hydrogenation under atmospheric
conditions
• The original and still a commonly practiced
form of hydrogenation
• This process is usually effected by adding
solid catalyst to a round bottom flask
• Hydrogen gas is then supplied from a H2-filled
balloon.
• Hydrogen uptake can be monitored, which can
be useful for monitoring progress of a
hydrogenation.
17. Hydrogenation under atmospheric
conditions
• In this method a round
bottom flask is equipped
with a condenser and a
bubbler (needle) for
hydrogen supply; the same
needle is used for nitrogen
purging
19. Batch hydrogenation at elevated
temperature and/or pressure
• Since many hydrogenation reactions
extremely sluggishly at atmospheric
temperature and pressure.
• Pressurized systems are popular. In
these cases, catalyst is added to a
solution of reactant under an inert
atmosphere in a pressure vessel.
• Hydrogen is added directly from a
cylinder or built in laboratory
hydrogen source
20. Continuous-Flow Hydrogenations
• Continuous-flow hydrogenations are safer options for
small as well as large scale laboratory hydrogenations.
• It is a superior as compared to batch hydrogenations in
terms of hydrogen handling, catalyst manipulation and
pressure.
• During continuous flow hydrogenations, the catalyst is
restricted in a closed cartridge and never comes in
contact with air which reduces flash fire and other
solvent/ catalyst hazards in a laboratory set-up.
21.
22. FACTORS AFFECTING
HYDROGENATION
• Independent Variables
1. Pressure
2. Temperature
3. Agitation
4. Catalyst concentration
• Dependent Variables
1. Trans fatty acids
2. Selectivity ratio
3. Hydrogenation rate
23. Hydrogenation of Alkenes
• The reaction of the carbon-carbon double bond
in alkenes with hydrogen in the presence of a
metal catalyst.
• This is called hydrogenation. It includes the
manufacture of margarine from animal or
vegetable fats and oils.
• Ethene reacts with hydrogen in the presence of a
finely divided nickel catalyst at a temperature of
about 150°C. Ethane is produced.
24. Catalysts
• Common catalysts used are insoluble metals
such as palladium in the form PdC, platinum in
the form PtO2, and nickel in the form Ra-Ni.
25.
26.
27. SOLVOLYSIS
• Solvolysis, a chemical reaction in which the
solvent, such as water or alcohol.
• Solvolytic reactions are usually substitution
reactions—i.e., reactions in which an atom or a
group of atoms in a molecule is replaced by
another atom or group of atoms.
• The solvents act as or produce electron-rich
atoms or groups of atoms (nucleophiles) that
displace an atom or group in the substrate
molecule.
28. • At high temperatures or in the presence of
strong bases, some solvents act as eliminating
agents, producing alkenes from alkyl halides.
• It is common practice to name solvolysis
reactions after the specific solvent, such as
“hydrolysis” when water is the reagent.
29. PART A-QUESTIONS
• Define following
Hydrolysis
Hydrogenation
Solvolysis
• Types of hydrolysis
• Methods of hydrogenation
• List out the Catalytic agents
30. PART B-QUESTIONS
• Explain the following process
Hydrolysis
Hydrogenation
Solvolysis
Methods of hydrogenation
