Given below are two statements :
Statement (I): According to the Law of Octaves, the elements were arranged in the increasing order of their atomic number.
Statement (II) : Meyer observed a periodically repeated pattern upon plotting physical properties of certain elements against their respective atomic numbers.
In the light of the above statements, choose the correct answer from the options given below :
Statement (I): According to the Law of Octaves, the elements were arranged in the increasing order of their atomic number.
Statement (II) : Meyer observed a periodically repeated pattern upon plotting physical properties of certain elements against their respective atomic numbers.
In the light of the above statements, choose the correct answer from the options given below :
- (A)Statement I is false but Statement II is true
- (B)Both Statement I and Statement II are true
- (C)Statement I is true but Statement II is false
- (D)Both Statement I and Statement II are false✓ Correct
Answer: (D)
Solution
Newlands' Law of Octaves arranged elements in order of increasing atomic weight, not atomic number — the concept of atomic number arrived decades later with Moseley — so Statement I is false. Lothar Meyer also plotted physical properties such as atomic volume, melting point and boiling point against atomic weight rather than atomic number, so Statement II is false as well. Both statements are false.
JEE Main · 2025 · 28 Jan 2025 · Shift 2 · Single correct option