Tag: basic concepts of chemistry

Questions Related to basic concepts of chemistry

On the basis of assumptions Dalton explain __________.

chemistry basic concepts of chemistry history of atomic model atomic theory of dalton daltons atomic theory

  1. Law of definite proportion.

  2. Law of conservation of mass.

  3. Law of combining volume.

  4. Law of reciprocal proportion.

Show answer
Correct Option: A

Choose the correct option :


Dalton's atomic theory suffered from _________.

chemistry basic concepts of chemistry history of atomic model atomic theory of dalton daltons atomic theory

  1. Atoms of the same or different types have a strong tendency to combine together to form a new group of atom

  2. The atom can no longer be considered indivisible

  3. Discovery of isotopes indicated that all atoms of the same element are not perfectly identical

  4. All of the above

Show answer
Correct Option: D
Explanation:

Drawbacks of Dalton's atomic theory:

1. The atom is further subdivided into protons, neutrons, electrons.

2. The atoms of same elements are not similar in all aspects. They may vary in mass and density. These are known as isotopes.

3. Atoms of different elements are not different in all aspects. Atoms of different elements that have the same atomic mass are called isobar.

4. According to Dalton atoms of different elements combine in simple whole-number ratio to form compounds. This is not seen in complex organic compounds.

5. This theory fails to explain the existence of allotropes.

On which basis later researches proved that Dalton's atomic theory was not wholly correct :

chemistry basic concepts of chemistry history of atomic model atomic theory of dalton daltons atomic theory

  1. An atom is the ultimate

  2. Discrete particle of matter

  3. Indivisible particle of matter

  4. All of the above

Show answer
Correct Option: D
Explanation:

Drawbacks of Dalton's atomic theory :


1. The atom is further subdivided into protons, neutrons, electrons.


2. The atoms of the same elements are not similar in all aspects. They may vary in mass and density. These are known as isotopes.

3. Atoms of different elements are not different in all aspects. Atoms of different elements that have the same atomic mass are called isobar.

4. According to Dalton atoms of different elements combine in simple whole-number ratio to form compounds. This is not seen in complex organic compounds.

5. This theory fails to explain the existence of allotropes.


Hence the correct option is D.

Law of constant proportion is given by _________.

chemistry basic concepts of chemistry history of atomic model atomic theory of dalton daltons atomic theory

  1. Thompson

  2. Dalton

  3. Joseph Louis Proust

  4. None of these

Show answer
Correct Option: C
Explanation:

Joseph Louis Proust had given the law of constant proportion.


The law of constant proportions states that chemical compounds are made up of elements that are present in a fixed ratio by mass. This implies that any pure sample of a compound, no matter the source, will always consist of the same elements that are present in the same ratio by mass. For example, pure water will always contain hydrogen and oxygen in a fixed mass ratio (a gram of water consists of approximately 0.11 grams of hydrogen and 0.88 grams of oxygen, the ratio is 1:8).

Hence, the correct option is $\text{C}$