The heaviest atom amongst the following is

Chlorine exists in two isotopic forms $^{35}Cl$ and $^{37}Cl$. If the average atomic mass of chlorine is $35.5$,what is the percentage abundance of these isotopes respectively?

At $STP$,if $5.6 \ L$ of a gas weighs $7.5 \ g$,then identify the gas.

What is meant by $1 \ amu$ or $1 \ u$?

Accurate determination of atomic masses is done with the instrument called as

An element has three isotopes and their isotopic weights are $11, 12, 13$ units,and their percentage of occurrence in nature is $80 \%, 15 \%, 5 \%$ respectively. Then the average atomic weight of the element will be $:-$