Sodium has an of $22.99*g*mol^-1$. How do I know this? Well, for a start it is printed on , a copy of which will be made available in every examination of chemistry and physics you sit........
And so we take the (dimensional) product..........
$22.99*g*cancel(mol^-1)xx0.05*cancel(mol)=??*g$, a bit over one gram...........
Typically, questions like these would also ask you to calculate the volume of dihydrogen gas evolved ......... Can you make this assessment?