Hi! so i've currently learned about the electronic configuration of elements. although i'd like to take 1 step ahead. i've been told that the first shell can hold a maximum of 2 electrons the second shell can hold a maximum of 8 and the 3rd shell too. however im curious how many electrons in the 4th and 5th shell? is there a pattern to this or number to memorise?

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.