Before turning on the heat for a microscale distillation, what should you confirm about the set-up? a. Secure connections at the joints.

b. Existence of some opening in the set-up.

c. Water is on in the condenser.

d. Presence of boiling chip in the sample

Existence of some opening in the setup

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 the answer is terrae but not 100 percent sure. ▓▬▬ §