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”.