Dalton's Atomic Theory - MCQ Practice Set

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01. According to Dalton's atomic theory, what are atoms considered as?
a) Tiny, divisible particles
b) Fundamental building blocks of matter
c) Mixtures of elements
d) Complex compounds
Answer: b) Fundamental building blocks of matter
Explanation: Dalton proposed that atoms are the fundamental building blocks of matter and cannot be further divided into smaller parts while retaining their chemical properties.

02. Which principle is consistent with Dalton's postulate that atoms can be rearranged, combined, or separated in chemical reactions?
a) Law of Definite Proportions
b) Law of Conservation of Mass
c) Law of Multiple Proportions
d) Avogadro's Law
Answer: b) Law of Conservation of Mass
Explanation: Dalton's postulate aligns with the Law of Conservation of Mass, which states that the total mass of the reactants must equal the total mass of the products in a chemical reaction.

03. What aspect of chemical compounds does Dalton's atomic theory explain?
a) Formation of compounds with varying proportions
b) Formation of compounds in fixed, simple, whole-number ratios
c) Formation of compounds with random compositions
d) Formation of compounds with no fixed properties
Answer: b) Formation of compounds in fixed, simple, whole-number ratios
Explanation: Dalton proposed that chemical compounds are formed when atoms of different elements combine in fixed, simple, whole-number ratios, consistent with the Law of Definite Proportions.

04. What aspect of atomic theory does Dalton's atomic theory fail to address, as described in the passage?
a) Chemical reactions involving atoms
b) Laws of gaseous volumes
c) Laws of electrochemistry
d) Laws of thermodynamics
Answer: b) Laws of gaseous volumes
Explanation: The passage mentions that Dalton's theory could not explain the laws of gaseous volumes, which were addressed by other scientists.

05. What did Dalton propose about the behavior of atoms in chemical reactions?
a) Atoms are created in chemical reactions
b) Atoms are destroyed in chemical reactions
c) Atoms are rearranged, combined, or separated in chemical reactions
d) Atoms remain unchanged in chemical reactions
Answer: c) Atoms are rearranged, combined, or separated in chemical reactions
Explanation: Dalton postulated that atoms are neither created nor destroyed in chemical reactions, but only rearranged to form new substances.

06. What is one of the limitations of Dalton's atomic theory concerning the composition of compounds?
a) Compounds always contain the same elements in the same proportion by mass.
b) Compounds do not need to combine in simple, whole-number ratios.
c) Compounds have varying atomic masses.
d) Compounds are made up of mixtures of elements.
Answer: b) Compounds do not need to combine in simple, whole-number ratios.
Explanation: Some complex organic compounds do not have simple ratios of component atoms, which Dalton's theory fails to account for.

07. Which concept, not addressed in Dalton's atomic theory, refers to atoms of different elements with the same mass number?
a) Isotopes
b) Isobars
c) Allotropes
d) Molecules
Answer: b) Isobars
Explanation: Isobars are atoms of different elements that have the same mass number, a concept not accounted for in Dalton's atomic theory.

08. What term describes the different forms of the same element with distinct properties, such as diamond and graphite?
a) Isotopes
b) Isobars
c) Allotropes
d) Ions
Answer: c) Allotropes
Explanation: Allotropes are different structural forms of the same element, such as diamond and graphite, with distinct properties but consist of atoms of the same type.

09. Which of the following is a limitation of Dalton's atomic theory concerning the atomic masses of isotopes?
a) All atoms of an element have identical masses and densities.
b) Atoms combine in fixed, whole-number ratios.
c) Atoms are indivisible.
d) Atoms of different elements have different properties.
Answer: a) All atoms of an element have identical masses and densities.
Explanation: Dalton's theory stated that all atoms of an element have identical masses and densities, which is a limitation because different isotopes of elements have different atomic masses.

10. What phenomenon, not explained by Dalton's atomic theory, refers to the differences in properties between diamond and graphite?
a) Isotopes
b) Isobars
c) Allotropy
d) Molecules
Answer: c) Allotropy
Explanation: Allotropy refers to different structural forms of the same element with distinct properties, such as diamond and graphite, which Dalton's theory did not account for.




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