What is the atomic mass of $Fe$?
Given abundance of ${}^{54}Fe = 10\%$,${}^{56}Fe = 85\%$,and ${}^{57}Fe = 5\%$.

In the chemical scale,the relative atomic mass of the naturally occurring isotopic mixture of oxygen atoms $({}^{16}O, {}^{17}O, {}^{18}O)$ is taken as:

The equivalent weight of a bivalent metal is $37.2$. The molecular weight of its chloride is

Calculate the molar mass of the following:
$(i)$ $H_2O$
$(ii)$ $CO_2$
$(iii)$ $CH_4$

$12 \ g$ of an element reacts with $32 \ g$ of oxygen. What is the equivalent weight of the element?

An element has two main isotopes of mass numbers $85$ and $87$. In nature,they occur in the ratio of $75\%$ and $25\%$ respectively. The atomic weight of the element will be approximately: