Acids produce hydrogen ions in water and have sour tastes, while bases produce hydroxide ions in water and have bitter tastes. Common acids include citric acid and hydrochloric acid, while common bases include sodium hydroxide and ammonia. Strong acids and bases fully dissociate in water, while weak acids and bases only partially dissociate. The pH scale measures how acidic or basic a solution is. Neutralization is the reaction between an acid and base that produces water and a salt. Indicators change color to determine if a solution is acidic or basic.

1. Acids Bases And Salts
Chapter-2

2. Acids
 An acid is a substance that produces hydrogen ions (H+)
when placed in aqueous solution .
 When acids/ ionic compounds are dissolved in water, the ions
split apart from each other
(Dissociation)

3. Properties of
Acids
Most acids…
 Taste sour
 React with many metals to form H2 gas
 Are corrosive
• Zinc Metal + Hydrochloric Acid  ??
Zn (s) + 2 HCl (aq)  H2 (g) + ZnCl2 (aq)

4. • Acetic Acid
 Vinegar
 Used as a preservative
• Carbonic Acid ( H2CO3) or Phosphoric Acid (H3PO4)
 Found in soft drinks
• Hydrochloric Acid (HCl)
 Found in our stomachs- aids in food digestion
• Citric Acid
 Found in citrus fruits
• Used as a preservative
• Lactic Acid
 Found in yogurt
 Produced by our muscles when they are overworked
COMMON ACIDS

5. BASES
• A base is a substance that produces hydroxide ions (OH-) when placed
in water.
• When bases/ ionic compounds are dissolved in water, the ions split
apart from each other.
(Dissociation)

6. PROPERTIES OF BASES
Most bases…
Taste bitter
Feel slippery
Are corrosive (appears to “eat away” materials
while reacting)
Have a chemical formula that ends with OH

7. COMMON BASES
o Ammonia
• Cleaners and fertilizers
 Sodium hydroxide
• Used in soaps and drain cleaners
 Magnesium hydroxide
• An ingredient found in antacids

8. STRONG/WEAK ACIDS & BASES
 When a strong acid/base dissolves in
water, nearly all of the acid/base
molecules will dissociate into ions
 The greater the ability to dissociate,
the more potential the acid or base
has for being dangerous because
there are more ions available to react
 When a weak acid/base dissolves in
water, only a small fraction of the
acid/base molecules dissociate
(dissociate partially)
 With less ions in solution, there is less
potential for danger because there
are less ions available to react
Hydrogen
Hydrogen

9. STRONG/WEAK ACIDS EXAMPLES
Strong Acids
1. HNO3 – nitric acid
2. H2SO4 – sulfuric acid – battery acid
3. HCl – hydrochloric acid – stomach acid
Weak Acids:
1. H3C6H5O7 –citric acid –citrus fruits
2. HC2H3O2 – acetic acid – vinegar

10. STRONG/WEAK BASES EXAMPLES
 Strong Bases:
1. NaOH – sodium hydroxide
2. Any alkali or alkaline earth metal with OH-
(i.e. KOH – potassium hydroxide)
 Weak Bases:
1. Al(OH)3 – aluminum hydroxide – often found in deodorants
2. NH4OH – ammonium hydroxide (ammonia) –used in many cleaning
products

11. CONCENTRATED AND DILUTE
SOLUTION
• CONCENTRATED SOLUTION – The solution which contain less amount of
water [as a solvent] is known as CONCENTRATED SOLUTION .
• DILUTE SOLUTION –The solution which contain more amount of water [as a
solvent ]is known as DILUTE SOLUTION .

12.  Indicators are used to determine if a substance is an acid or a base
 An indicator changes a specific color when in the presence of an acid
or a base
 Litmus Paper: indicator made of a special filter paper that contains
dyes extracted from lichens (the crusty “stuff” that grows in rocks)
Blue litmus turns red in an ACID
Red litmus turns blue in a BASE
INDICATORS

13. PH SCALE
The pH scale can also help us classify solutions as acids or
bases
pH is a measure of the amount of H+ ions in a solution
(potential hydrogen)
 The more H+ ions, the lower the pH, the more acidic the
solution

14. NEUTRALIZATION
Neutralization is a chemical reaction between an
acid and a base that takes place in a water
solution
When acids and bases react, the H+ ions from the
acid react with the OH- ions from the base to form
HOH (H2O - water!)
The overall pH becomes “neutral”

15. SALTS
The ions that are left behind after the H+ and
OH- ions form water, combine to form a salt.
A salt is a compound that forms when the
negative ions from the acid combine with the
positive ions from the base.
Acid + Base  Water + Salt
HCl(aq) + KOH(aq)  H2O(l) + KCl(aq)

16. Made By :- AyUsH gUpTa
CLASS :- X-B
ROLL NO. :- 06