Question

what is atomic number consider to be a more appropriate parameter than atomic mass for the classification of elements in a periodic table?​

Answer 1

Atomic number

Its because atomic number increases uniformly by 1 unit unlike atomic mass and also when arranging ascendingly with respect to atomic number, elements show similar properties periodically (at regular and same intervals)

Answer 2

atomic number consider to be a more appropriate parameter than atomic mass for the classification of elements in a periodic table because isotopes find place and also

atomic mass is sum of protons/electron and neutrons but atomic number depends on only electron/proton and also the reactivity of element is determined by no. of electron so atomic number is important than mass