Can the following groups of elements be classified as Dobereiner's Triads. i] Na, Si, Cl "" ii] Be, Mg, CaAtomic mass of Be - 9. Na - 23, Mg -24, Si - 28, CI - 35, Ca - 40. Justify your answer.

Can the following groups of elements be classified as Dobereiner's Tri

1.	Can the following groups of elements be classified as Dobereiner's Triads. i] Na, Si, Cl "" ii] Be, Mg, CaAtomic mass of Be - 9. Na - 23, Mg -24, Si - 28, CI - 35, Ca - 40. Justify your answer.
Answer» Solution :i] `Na-23, Si – 28, CI - 35` ATOMIC mass of `Si = (23+35)/2 = 58/2 = 29` II] `Be-9, Mg -24, CA = 40` Atomic mass of Mg = `(40+9)/2 =49/2 = 24.5` i) They cannot be classified as DOBEREINER triads because they donot resemble with each other, though atomic mass of Si is the AVERAGE of Na and CI. ii) It can be classified as Dobereiner.s triads because the elements resemble each other.