Newland’s Law of Octaves
According to Newland’s Law of Octaves elements arranged in the group of 8 elements and every 8th element is similar to the 1st element.
Li Be B C N O F
Na Mg Al Si P S Cl
Drawback of Newland’s Law of Octaves :
Heavy elements do not follow this law, inert gases disturb the order of octave.
Lother Meyer Curves
In 1869, Lother Meyer derived following conclusion by obtaining information from graph between the atomic weight at x-axis and atomic volume at y-axis.
1. Elements which have similar properties found on the same position on the graph curves.
2. All alkali metals like Li, Na, K, Rb, Cs, and Fr found at highest peak of curve.
3. Halogens like F, Cl, Br and I are found on ascending portion of curve.
4. Alkaline earth metals like Mg, Ca, Sr, Ba and Ra are found on descending portion of curve.
5. Elements which do not melt easily like Be, B, C, Al, Si, Cu etc. are found at lowest point of curve.
On the basis of above conclusions Lother Meyer give periodic Law:
According to Lother Meyer periodic law – “Atomic volume of elements are periodic function of their atomic weights”.