Question

What is the relative mass of 1.6 moles of Mg to 1.6 moles of Pd?

Answer 1

As the number of moles is the same the relative masses will be in the same ratio as the atomic masses of the two elements. (Mg = 24.3 Pd = 106.42)

We know that Number of moles , n = mass/molar mass

So mass(m) = number of moles(n) x molar mass(M)

Molar mass of Mg = 24.3 g/mol

Molar mass of Pd = 106.4 g/mol
So mass of Mg , m_Mg = n_Mg x M _Mg

                                 = 1.6 mol x 24.3(g/mol)

                                 = 38.9 g

mass of Pd , m_Pd = n_Pd x M _Pd

                          = 1.6 mol x 106.4(g/mol)

                         = 170.2 g

Therefore the relative mass of 1.6 moles of Mg is 38.9 g

                          and that of 1.6 moles of Pd is 170.2 g