J.W.Dobereiner was a …… chemist
a) German
b) English
c) Russian
d) Italian
Chemically same elements were named..…… by J.W.Dobereiner.
a) octaves
b) triads
c) a & b both
d) all of these
Explanation:Dobereiner stated in his law of triads that the arithmetic mean of the atomic masses of the first and third element in a triad would be approximately equal to the atomic mass of the second element in that triad.
In triads the atomic weight of the middle element was …… of the atomic weights of other two elements.
a) arithmetic mean
b) geometric mean
c) summation
d) none of these
J.Newlands was ……… chemist.
a) English
b) German
c) Italian
d) Russian
J.Newlands classified elements in order of their increasing …………..
a) atomic mass
b) atomic number
c) atomicity
d) molecular mass
Octaves were named by ……..
a)J.Newlands
b) Mendeleev
c) J.W.Dobereiner
d) Lavoisier
Explanation:Law of octaves, in chemistry, the generalization made by the English chemist J.A.R. Newlands in 1865 that, if the chemical elements are arranged according to increasing atomic weight, those with similar physical and chemical properties occur after each interval of seven elements.
