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1. Definition of Acid and Bases: 1.1 Arrhenius definition of acid and base: Arrhenius Acid: The

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1. Definition of Acid and Bases:
1.1 Arrhenius definition of acid and base:
Arrhenius Acid:
The substance or a compound which gives H+ ions in aqueous solution Arrhenius base: Base is a substance or compound that produces OH- ions in aqueous solutions. Chemists have known for some time that the H+ ion doesn’t exist in aqueous solutions as an independent species. The modernized Arrhenius definition of acid is that they are substances that produce H3O+ ions in aqueous solutions. It did not take longer for chemist to find other problems with the Arrhenius definition. In practical terms, the OH- ion is far from being the only base.

1.2 Bronsted-Lowry definition:
Bronsted-Lowery definitions acid and a base, …show more content…

Example: HN03 dissociates completely in water to form H+ and N031-.
The reaction is HNO3 → H+ + N031-
A 0.01 M solution of nitric acid contains 0.01 M of H+ and 0.01 M N03- ions and almost no HN03 molecules. The pH of the solution would be 2.0. Following 6 are strong acids
1. HCl
2. H2SO4
3. HNO3
4. HClO4
5. HBr
6. HI

2. Weak acids:
A weak acid only partially dissociates in water to give H+ and the anion is called weak acid.
Example: HF dissociates in water to give H+ and F-. It is a weak acid.
HF ↔ H+ + F-
1) Strong Bases:
They dissociate 100% into the cation and OH- (hydroxide ion).
Example:
NaOH → Na+ + OH-
2. Weak Bases:
Weak bases do not furnish OH- ions by dissociation. They react with water to furnish the OH- ions. For example, When a weak base reacts with water the OH- comes from the water and the remaining H+ attaches itself to the weak base, giving a weak acid as one of the products. You may think of it as a two-step reaction similar to the hydrolysis of water by cations to give acid solutions.
NH3 + H2O → NH4+ + OH-
Reactions of Acids:
A) Reaction of acid with metals: Acid react with metals such as
Metal + acid ==> a salt + hydrogen Example:
Grey-silvery solid zinc dissolves with effervescence to evolve hydrogen gas and leave a colourless solution of the salt zinc chloride.
Zn + 2HCl ==> ZnCl2 + H2
Zn + 2HCl ==>ZnCl2 + H2
. A strip of magnesium ribbon

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