Question

10^22 atoms of an element 'x' are found to have a mass of 930mg. Calculate the molar mass of the element 'x'.

Answer 1

1 mole = 6.022 * 10^23 atoms

No. moles = given mass / molar mass

Molecular mass = given mass / avagadro number * given atoms
              
                          = 0.930 g * 6.022 * 10^23 / 10^22
                          = 5.6 * 10 g 

(* = multiply)

Answer 2

Explanation:

The given mass of substance 'X' is m = 930 mg = 0.930 g,          

It is known that 1 mole contains $6.022 \times 10 ^{23}$ atoms.

Therefore, there will be $\frac{6.022 \times 10 ^{23}}{1 \times 10^{22}}$ atoms in the given substance 'X'.

Hence, calculate the molar mass as follows.

         Molar mass = $mass \times atoms$

                             = $0.930 g \times \frac{6.022 \times 10 ^{23}}{1 \times 10^{22}}$

                             = 0.930 g \times 60.22 atoms/mol

                             = 56.00 g/mol

Thus, we can conclude that molar mass of substance 'X' is 56.00 g/mol.