Name any two pairs of elements which were adjusted by Newlands in the same slot.

Which among the following elements has the largest atomic radii?

The scientist who showed that the atomic number of an element is a more fundamental property than its atomic mass is:

State whether the following statement is true or false: In $1913$,Dmitri Ivanovich Mendeleev showed that the atomic number of an element is a more fundamental property than its atomic mass.

Atomic radii of the elements of the second period are given below :

Period $II$ elements	$B$	$Be$	$O$	$N$	$Li$	$C$
Atomic radius $(pm)$	$88$	$111$	$66$	$74$	$152$	$77$

$(i)$ Arrange them in decreasing order of their atomic radii.
$(ii)$ Are the elements now arranged in the pattern of a period in the Periodic Table?
$(iii)$ Which elements have the largest and the smallest atoms?
$(iv)$ How does the atomic radius change as you go from left to right in a period?

Elements have been arranged in the following sequence on the basis of their increasing atomic masses.
$F, Na, Mg, Al, Si, P, S, Cl, Ar, K$
$(a)$ Pick two sets of elements which have similar properties.
$(b)$ The given sequence represents which law of classification of elements?