In Newlands’ Octaves, the properties of lithium and ________ were found to be the same.
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. sodium.
In Newlands’ Law of Octaves, the properties of lithium (Li) and sodium (Na) were observed to be similar, as they appeared at intervals of eight elements, mirroring musical octaves. This early periodic classification (1864) highlighted repeating patterns but was limited to known elements then (e.g., Li (3rd) and Na (11th)).
Limitation: Failed for heavier elements like transition metals.