If you need to measure the mass of a greeting card you are sending to a friend through the mail, what unit of measurement would you use?

The best unit of measurement will be the gram (g).

Explanation:

A typical letter has a mass of about 12 g including the envelop (that is if the letter has only one sheet of paper).

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.

50.23 i believe is correct but don't quote me on that.