Why is mendeleev the father of the periodic table

Because

Explanation:

He started the development of the periodic table. He arranged the chemical elements by their atomic mass. He also predicted the discovery of other elements, and left some spaces open in his periodic table for them.

sry but any answer choices

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.