Definitions and MCQs of Ninth class chemistry (acids, bases and salts)
1. Chapter 9
Acids, Bases and Salts
(I do not own any business but the entire
world is my own where Almighty Allah is to
be felt and Muhammad (s.a.w) to be
followed)
Chemistry Def. & MCQs Dr. Sajid Ali Talpur
2. Definitions
1. Acid: -A compound having usually sour taste
and capable of neutralizing alkalis and
reddening blue litmus paper, containing
hydrogen that can be replaced by a metal or any
other electropositive atom to form salt, or
containing an atom that can accept electrons
from a base.
2. Base: - A base is a substance that can accept
hydrogen ions or more generally, donates
electrons pairs.
3. Salt: -the ionic substance that result from the
neutralization of an acid with a base.
4. Ph: - A measure of the acidity or alkalinity of a
solution, numerically equal to 7 for neutral
solutions, increasing with increasing alkalinity
and decreasing with increasing acidity.
5. Arrhenius Theory: It states that an acid can be
defined as a substance that yields hydrogen ions
when dissolved in water. A base can be defined
as a substance which yields hydroxide ions
when dissolved in water.
6. Bronsted Lowery Theory: It states that an acid
is a substance having a tendency to donate one
or more protons and a base is a substance
having a tendency to accept protons.
Chemistry Def. & MCQs Dr. Sajid Ali Talpur
3. 7. Lewis Theory: It states that an acid is any
species (molecule or ion) which can accept a
pair of electrons and a base is any species
(molecule or ion) which can donate a pair of
electrons.
8. Titration: -titration is the quantitative
measurement of an analyte in solution by
completely reaction with reagent solution.
Indicators: -color showing organic compounds.
OR for acid-base titrations, organic compounds
that exhibit different colors in solution of
different acidities; used to determine the point at
which the reaction between two solutes is
complete.
9. Buffer: -any substance that prevents changes in
pH is known as buffer.
10. Neutralization: -when the two substances (acid
and base) having opposed properties are allowed
to react, salt and water are produced. The
reaction is known as neutralization.
Chemistry Def. & MCQs Dr. Sajid Ali Talpur
4. Multiple Choice Questions:
1. Ascorbic acid is the other name of:
a) Vitamin A b) Vitamin B
c) Vitamin C d) Vitamin D
2. all are the properties of acids except:
a) sour in taste b) smooth in touch
c) proton donor d) electrons acceptor
3. the common acid in stomach is:
a) HCl b) H2SO4
c) HNO3 d) H3PO4
4. The consumption of …… is an index to the state
of civilization and prosperity of a country:
a) HCl b) H2SO4
c) HNO3 d) H3PO4
5. the important acid for making explosive
materials and fertilizers is:
a) HCl b) H2SO4
c) HNO3 d) H3PO4
6. the souring of milk produces.
a) citric acid b) lactic acid
c) acetic acid d) fumaric acid
7. lemon, oranges, grape fruits contain:
a) citric acid b) lactic acid
c) acetic acid d) fumaric acid
Chemistry Def. & MCQs Dr. Sajid Ali Talpur
5. 8. all are the properties of bases except:
a) bitter in taste
b) aqueous solution conducts electricity
c) undergo neutralization with acids
d) turn litmus paper to red.
Q 9 – 14
Select from the terms below:
a) Arrhenius Theory b) Bronsted –lowery
c) Lewis concept d) N.O.T
9. Bases are proton acceptors.
10. acids are sour in taste
11. acids are H+
ions donor
12. bases turn litmus paper to blue
13. ammonia is base
14. bases are electron donors
15. all are weak acids except:
a) sulphuric acid b ) acetic acid
c) formic acid d) phosphoric acid
16. which one is the normal salt:
a) NaCl b) NaHSO4
c) KHCO3 d) Mg(OH) Cl
17. which one is not double salt:
a) potash alum b) chrome alum
c) Mohor’s salt d) table salt
Chemistry Def. & MCQs Dr. Sajid Ali Talpur
6. Q18 -22
Select from the terms below:
a) Sodium carbonate b) backing soda
c) copper sulphate d) Epsom salt
e) potash alum f) N.O.T
18. it is a common double salt
19. used as antiacid and fire extinguishers
20. used as germicide, insecticide and in paint and
varnish industry
21. it is used in softening of water, glass industry
and as cleaning agent
22. used as anticeptic and mouth wash
23. water is not:
a) universal solvent b) liquid
c) present in urine d) amphoteric molecule
e) N.O.T
24. The number of moles of solute dissolved per
liter of solution is:
a) molarity b) molality
c) titration d) pH
25. negative logarithm of hydrogen ion
concentration is:
a) molarity b) molality
c) titration d) pH
Chemistry Def. & MCQs Dr. Sajid Ali Talpur
7. 26. it is important for an analytical chemist
a) molarity b) molality
c) titration d) pH
Q 27 – 32
Select from the terms below
a) 0 b) 5-7
c) 7 d) 7.4
e) 14
27. it is the neutral pH
28. the pH of water is :
29. it is the highly acidic Ph
30. the pH of urine is:
31. the pH of blood is
32. pH + p OH = ?
33. Methyl orange produce…. Color in acidic
solution
a) red b) green
c) yellow d) pink
34. a solution whose molarity or strength is known
is called standard solution:
a) true b) false
Chemistry Def. & MCQs Dr. Sajid Ali Talpur
8. 35. low p H of blood causes diabetes, diarrhea,
vomiting.
a) true b) false
36. water and CO2 are produced as a result of
neutralization:
a) true b) false
Answer Key
1 C 2 B 3 A
4 B 5 C 6 B
7 A 8 D 9 B
10 D 11 A 12 D
13 B 14 C 15 A
16 A 17 D 18 E
19 B 20 C 21 A
22 E 23 E 24 C
25 C 26 A 27 B
28 D 29 E 30 A
31 D 32 C 33 A
34 A 35 B 36 B
Chemistry Def. & MCQs Dr. Sajid Ali Talpur