1. La configuración electrónica del elemento Z 13 es: A. 1s2 2s2
B. 1s2 1s2 1p6 3s1
C. 1s2 1p4 1d5
D. 1s2 2s2 2p6 3s2 3p1

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.