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


i. Pick two sets of elements which have similar properties.


ii. The given sequence represents which law of classification of elements?

i. Na and K -Alkaline Metals


F and Cl- Halogens


Explanation: Na and K of group 1 are called alkaline metals and share the same properties. They are highly metallic and have large atomic sizes.


F and Cl are halogens of group 7. They are all gases and are highly electronegative with small atomic sizes.


ii. The given sequence represents the periodic law.


Explanation: According to the periodic law, the elements are arranged according to the increasing order of atomic masses. Since in the given sequence elements are arranged according to that we can apply this law here.


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