Wwhat do these substances have in common? apple juice helium gas salt water copper wire a. they are composed of atoms. b. they are pure substances. c. they are composed of molecules. d. they are compounds.

Answer; Option A is correct

Explanation:

All the given four substance are matter :

But all of them are composed of atoms.

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.

it is the most commonly accepted one