Substances which have identical chemical properties but differ in atomic weights are called

The number of protons,neutrons and electrons in ${ }_{71}^{175} Lu$,respectively,are:

The electronic configuration of a divalent metal ion $M^{2+}$ is $2, 8, 14$ and its atomic mass is $58 \, a.m.u.$ What is the number of neutrons in its nucleus?

The number of protons,neutrons and electrons in ${}^{13}_{6}C$ respectively are

An atom has a mass number of $25$ and contains $13$ neutrons in its nucleus. What is the charge of its ion if it forms a stable octet?

Calculate the number of protons,neutrons and electrons in $_{35}^{80}Br$.