SHORT DESCRIPTION CONCERNING BASES

1. BASEBase is a substance with at least one lone pair, and can exchange it during
chemical reaction….
It’s the substance when dissolved in water, rises the ph value above 7
bases are substances that, in aqueous solution, release hydroxide (OH−)
ions, are slippery to the touch, can taste bitter if an alkali,[1] change the
color of indicators (e.g., turn red litmus paper blue), react with acids to
form salts, promote certain chemical reactions (base catalysis), accept
protons from any proton donor or contain completely or partially
displaceable OH− ions.
Examples of bases are the hydroxides of the alkali metals and the alkaline
earth metals (NaOH, Ca(OH)2, etc., see alkali hydroxide and alkaline earth
hydroxide).

2. PROPERTIES OF BASES
General properties of bases include:
• Concentrated or strong bases are caustic on organic matter and
react violently with acidic substances.
• Aqueous solutions or molten bases dissociate in ions and
conduct electricity.
• Reactions with indicators: bases turn red litmus paper blue,
phenolphthalein pink, keep bromothymol blue in its natural colour of
blue, and turn methyl orange yellow.
• The pH of a basic solution at standard conditions is greater
than seven.
• Bases are bitter in taste.

3. CLASSIFICATION OF BASES
ACCORDING TO STRENGTH
• Strong bases:
A strong base is a basic chemical compound that can remove a proton (H+) from
(or deprotonate) a molecule of even a very weak acid (such as water) in an acid-
base reaction. Common examples of strong bases include hydroxides of alkali
metals and alkaline earth metals, like NaOH and Ca(OH)2, respectively.
• Superbases:
Group 1 salts of carbanions, amides, and hydrides tend to be even stronger bases
due to the extreme weakness of their conjugate acids, which are stable
hydrocarbons, amines, and dihydrogen. Usually these bases are created by adding
pure alkali metals such as sodium into the conjugate acid. They are called
superbases, and it is impossible to keep them in water solution because they are
stronger bases than the hydroxide ion. As such, they deprotonate the conjugate
acid water. For example, the ethoxide ion (conjugate base of ethanol) in the
presence of water undergoes this reaction.
Example of superbase; Lithium bis(trimethylsilyl)amide, Sodium hydride, Sodium

4. • Neutral base:
When a neutral base forms a bond with a neutral acid, a condition of electric
stress occurs.The acid and the base share the electron pair that formerly
only belonged to the base.As a result, a high dipole moment is created,
which can only be destroyed by rearranging the molecules.
• Weak bases:
A weak base is one which does not fully ionize in an aqueous solution, or in
which protonation is incomplete. Most of organic bases are weak base

5. CLASSIFICATION ACCORDING TO
NATURE/SOURCES
•Organic bases: originate from living
organism e.g amines and pyridines
•Non organic/mineral bases: its
sources are non living organism

6. ACIDITY OF BASESThe number of ionizable hydroxide (OH-) ions present in one molecule of base is called
the acidity of bases.[13] On the basis of acidity bases can be classified into three types:
monoacidic, diacidic and triacidic.
Monoacidic bases
When one molecule of a base via complete ionization produces one hydroxide ion, the
base is said to be a monoacidic base. Examples of monoacidic bases are:Sodium
hydroxide, potassium hydroxide, silver hydroxide, ammonium hydroxide, etc.
Diacidic bases
When one molecule of base via complete ionization produces two hydroxide ions, the
base is said to be diacidic. Examples of diacidic bases are:Barium hydroxide, magnesium
hydroxide, calcium hydroxide, zinc hydroxide, iron(II) hydroxide, tin(II) hydroxide,
lead(II) hydroxide, copper(II) hydroxide, etc.
Triacidic bases
When one molecule of base via complete ionization produces three hydroxide ions, the
base is said to be triacidic. Examples of triacidic bases are: Aluminium hydroxide,
ferrous hydroxide, Gold Trihydroxide,

7. PHARMACEUTICAL USES OF THE
BASES
Bases act as an ant-acids:sodium hydroxide,aluminum hydroxide
and magnesium hydroxide.
Bases act as PH risers for some medicine to yield a desired effect in
the body.EG sodium carbonate
Bases act also as dis-infectants. eg:formaldehyde
Bases such as sodium hydroxide soften water and make it suitable
for pharmaceutical preparations.

8. PARTICIPANTS
•ASHRAF .J. KILANDE
•HANCE .A. PONERA
•ALFRED .M.NDUNGURU
•ADVODIA .A.KAMUGISHA
•SAFARI .S.KALEGO
•SUNDAY .S.TUMBO
•ALEX .M.BAZILIO

9. THANK
YOU