1. In Down's cell used for the extraction sodium metal, the anode and the cathode are screened with gauze diaphragm in order to A. Obtain screened products
B. Obtain cheap products
C. Separate the product from reacting
D. Obey conventional rule of electrolysis​

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.

i think it's letter a.