Question

What is the mass of $38.4$ mol of the element nickel?

Answer 1

We know that as we know, the molar mass of any element is the weight of one mole of that element. The molar mass of an element is the average of molar masses of all the isotopes of that element which exists in the atmosphere.

Complete answer:
Every ion, or an atom of an element, is bound to have a specific value of mass; in a similar way, every mole of any substance provided it is pure in nature, also would have definite mass. The mass of a single mole of an atom from a pure element in terms of grams will be equivalent to the atomic mass of the same element in terms of grams per mole in atomic mass units . Although mass can be expressed as both and, the unit of is known to have more usefulness in the system of units for the laboratory purposes.
Nickel metal has a molar mass of $58.69\cdot g\cdot mo{{l}^{-1}}.$
And thus the mass of the given quantity $=Number\text{ }of\text{ }moles\text{ }\times \text{ }Molar\text{ }Mass\text{ }$
Substituting the values in above equation/formula;
$58.69\cdot g\cdot mo{{l}^{-1}}\times 38.4\cdot mol~=~2.2kg$
Therefore, the mass of $38.4$ mol of the element nickel is $2.2kg$.

Note:
Remember that the molar mass of an element includes the fact that it is the mass of one mole of that element, meaning, it is the mass of atoms of that element. The concept of molar mass is used in various areas for calculation of concentration of a solution in terms of molarity, molality, or simply for the calculation of number of moles of that substance present.