Question

The relative atomic masses of nickel, cobalt, and iron are $58.70,$ $58.9332$ and $55.847,$ respectively, which element has the greatest mass? The least mass?

Answer 1

Hint: The atomic mass is the mass of a single atom of an element. The unit of atomic mass is amu or atomic mass unit. The atomic mass of each element is specific. Also, atomic masses are numerically equal to molar masses (mass in one mole of an element or molecule).

Complete answer:
One mole of iron contains $58.70gram$ weight.
One mole of cobalt contains $58.9332gram$ weight.
One mole of iron contains $55.847gram$ weight.
Now comparing all three weights, the order will be $58.9332g>58.70g>55.847g$
So, the element that has the greatest mass is cobalt and the element with least mass is iron, nickel being intermediate.

Note:
The molar mass of elements can be used to compare their relative masses. The element with highest molar mass will have the highest relative mass and element with lowest molar mass will have the lowest relative mass.