Welcome to Learn Chemistry by Inam Jazbi! Are you ready to test your knowledge of Fundamental Concepts of Chemistry – Unit #1? 🌟 Here you’ll find the most repeated and conceptual MCQs selected from past papers and model tests for Class XI Chemistry 2025. These questions cover important topics like mole concept, atomic mass, empirical formula, and chemical calculations — perfect for smart revision and quick testing before exams. Try this quiz and challenge yourself to score 100%!
MCQs on Introduction to Fundamental Concepts of Chemistry
XI Chemistry Unit 1 MCQs
Class 11 Chemistry Past Paper Questions
Mole Concept and Atomic Mass MCQs
Chemistry Objective Test Questions 2025
#ChemistryMCQs #XIClassChemistry #FundamentalConcepts #ChemistryQuiz #LearnChemistry #InamJazbi #Chemistry2025 #Class11
Boost your Chemistry prep with important MCQs on Introduction to Fundamental Concepts of Chemistry (Unit #1). Based on past papers for Class XI Chemistry 2025 — perfect for exam practice!
1. Which
one of the following statements is incorrect regarding mole concept?
(a)
|
A mole is the gram atomic or gram molecular mass or gram formula mass of a substance. |
(b)
|
1 mole of all elements contains
6.02 x 1023 particles irrespective of their states.
|
(c)
|
1 mole of all gases at s.t.p.
occupies 22.4 m3.
|
(d)
|
11.2 dm3 of hydrogen
gas at s.t.p. weighs 1 g.
|
2. Which
one of the following statements is incorrect regarding empirical formula?
(a)
|
It shows the simplest atomic
ratio.
|
(b)
|
Empirical formula of acetic
acid and glucose is CH2O.
|
(c)
|
Ionic or inorganic compounds
are usually represented by their empirical formulae.
|
(d)
|
It is an integral multiple of
molecular formula.
|
3. Which
one of the following statements is false regarding molar volume?
(a)
|
It is the volume occupied by 1
mole of any gas at s.t.p.
|
(b)
|
Its value is same at all
temperature and pressures.
|
(c)
|
Its value is 22.4 dm3 (liter)
or 22400 cm3 (ml) or 0.0224 m3.
|
(d)
|
Its value is computed by using
expression RT/P.
|
4. An
element has an atomic number of 11, the element is:
(a)
|
A metal with oxidation number
of +1.
|
(b)
|
A metal with an oxidation
number of +2.
|
(c)
|
An inert gas.
|
(d)
|
A non-metal with oxidation
number of -1.
|
5. Isotopes
differ in:
(a)
|
Arrangement of electrons in
orbitals.
|
(b)
|
The extent to which they may be
affected in electromagnetic field.
|
(c)
|
Properties which depend upon
mass
|
(d)
|
Chemical properties.
|
6. Which
one of the following statements is not true?
(a)
|
Isotopes with even atomic
masses are comparatively abundant.
|
(b)
|
Isotopes with odd atomic masses
are comparatively abundant.
|
(c)
|
Isotopes
with even atomic masses and even atomic numbers are comparatively abundant.
|
(d)
|
Isotopes
with even atomic masses and odd atomic numbers are comparatively abundant.
|
7. Many
elements have fractional atomic masses. This is because:
(a)
|
The mass of the atom is itself
fractional.
|
(b)
|
Atomic masses are average
masses of isobars.
|
(c)
|
Atomic masses are average
masses of isotopes.
|
(d)
|
Atomic
masses are average masses of isotopes proportional to their relative
abundance.
|
8. A
limiting reactant is the one which:
(a)
|
Is taken lesser quantity in
volume compared to the other reactants.
|
(b)
|
Is taken in lesser quantity
grams as compared to other reactants.
|
(c)
|
Produces the minimum amount of
the product under consideration.
|
(d)
|
Gives the maximum amount of the
product which is required.
|
9. Which
one of the following statement is not true?
(a)
|
The empirical and molecular
formulae of some compound are same.
|
(b)
|
Stoichiometric calculations can
only be done if no side reaction occurs.
|
(c)
|
A limiting reactant is consumed
at the end of the reaction.
|
(d)
|
Actual yield is always greater
than the theoretical yield.
|
10. Which
one of the following statement is not true?
(a)
|
In stoichiometric calculations,
low of definite proportions is definitely obeyed.
|
(b)
|
Isotopes of an element differ in
number of protons and so their masses are different.
|
(c)
|
Stoichiometric
amounts are the amounts of reactants and products in a balanced chemical equation.
|
(d)
|
Isotones are atoms of the
element having same number of neutrons.
|
11. A
quantity containing Avogadro’s number of particles is called:
(a)
|
Gram atom
|
(b)
|
Gram molecule
|
(c)
|
Mole
|
(d)
|
Gram formula
|
12. One
mole of hydrogen gas at s.t.p. contains how many atoms?
(a)
|
6.02x1023
|
(b)
|
3.01x1024
|
(c)
|
1.2x1024
|
(d)
|
12.04x1046
|
13. how many significant figures are
contained in 0.00050890400?
(a)
|
6
|
(b)
|
4
|
(c)
|
8
|
(d)
|
11
|
14. 16
g of oxygen has a volume of:
(a)
|
22.4 dm3
|
(b)
|
11.2 dm3
|
(c)
|
5.6 dm3
|
(d)
|
22400 cm3
|
15. 11.2
dm3 of Cl2 gas at s.t.p. weighs:
(a)
|
71g
|
(b)
|
17 g
|
(c)
|
35.5 g
|
(d)
|
37 g
|
16. Which
one of the following represents the value of 1 a.m.u.?
(a)
|
1.667x10-24 g
|
(b)
|
1.667x10-23 g
|
(c)
|
1.667x10-27 g
|
(d)
|
1.667x10-28 g
|
17. What
is the ratio of the weight of water formed to the weight of Hydrogen used in
the formation of water?
(a)
|
1 : 8
|
(b)
|
1 : 9
|
(c)
|
8 : 1
|
(d)
|
9 : 1
|
18. The
percentage of which of the following element in an organic compound cannot be measured directly?
(a)
|
Carbon
|
(b)
|
Hydrogen
|
(c)
|
Oxygen
|
(d)
|
Sulphur
|
19. Stoichiometric
calculation of a reaction gives us …………yield.
(a)
|
Actual
|
(b)
|
Theoretical
|
(c)
|
Both a and b
|
(d)
|
None of the above
|
20. Actual
yield is always …………. than the theoretical yield.
(a)
|
More
|
(b)
|
Less
|
(c)
|
Both a and b
|
(d)
|
None of the above
|
21. The
mass of one mole of electrons is:
(a)
|
1.008 mg
|
(b)
|
0.55 mg
|
(c)
|
0.184 mg
|
(d)
|
1.673 mg
|
22. The
number of moles of CO2 which contain 8.0 g of oxygen:
(a)
|
0.25
|
(b)
|
0.50
|
(c)
|
1.0
|
(d)
|
1.50
|
23. The
largest number of molecules are present in:
(a)
|
3.6 g of water
|
(b)
|
4.8 g of C2H5OH
|
(c)
|
2.8g of CO
|
(d)
|
5.4 g of N2O5
|
24. One
mole of SO2 contains:
(a)
|
6.02 x 1023 atoms of
oxygen
|
(b)
|
6.02 x 1023 atoms of sulphur
|
(c)
|
18.1 x 10 23
molecules of SO2
|
(d)
|
4 gram atoms of SO2
|
25. The
formula of KAl(SO4)2 represents a total of:
(a)
|
6 atoms
|
(b)
|
7 atoms
|
(c)
|
12 atoms
|
(d)
|
14 atoms
|
26. How
many neutrons are contained in the nucleus of an element with Z=27 and A= 59:
(a)
|
27
|
(b)
|
32
|
(c)
|
59
|
(d)
|
86
|
27. How
many gram of NaOH are needed to make 1000g of a 5% solution?
(a)
|
5g
|
(b)
|
500g
|
(c)
|
40g
|
(d)
|
50g
|
28. Chlorine
atom and chloride ions
(a)
|
Have same number of protons
|
(b)
|
Have same number of electrons
|
(c)
|
Are allotropes of chlorine
|
(d)
|
Are chemically identical
|
29. Which
of the following formula represents an acid anhydride?
(a)
|
CaO
|
(b)
|
H2O
|
(c)
|
H2SO4
|
(d)
|
SO3
|
30. Which
of the following formula represents a basic anhydride?
(a)
|
MgO
|
(b)
|
CrO3
|
(c)
|
CO
|
(d)
|
NO
|
31. The
basic oxide in the given list is:
(a)
|
N2O5
|
(b)
|
P4O6
|
(c)
|
Sb4O6
|
(d)
|
Bi2O3
|
32. If an element M forms an oxide with formula MO, which of the
following is a correct formula:
(a)
|
MCl
|
(b)
|
MS
|
(c)
|
MCl2
|
(d)
|
Both b and c
|
33. nm
is …………. than μm.
(a)
|
Equal to
|
(b)
|
Less
|
(c)
|
Greater
|
(d)
|
All of the above
|
34. Which
one is large than dm3?
(a)
|
cm3
|
(b)
|
Liter
|
(c)
|
m3
|
(d)
|
ml
|
35. The
decimal equivalent of 1/60 to three significant figures is:
(a)
|
0.156
|
(b)
|
0.0166
|
(c)
|
0.00166
|
(d)
|
1.666 x10−2
|
Tags
Chemistry Quiz 2025
Chemistry Unit 1 Test
ECAT
Fundamental Concepts of Chemistry MCQs
MCQs on Chapter 1Fundamental Concepts of Chemistry 1st Year
MDCAT
Mole Concept MCQs
Past Paper Chemistry Questions