The molecular weight of LiF is 26:

Atomic mass of Li + Atomic mass of F

= 7 + 19

= 26

We can also say that one mole of LiF is equal to 26 grams.

Now, if 26 grams equal 1 mole, how many moles do 39 grams contain? Let's see:

z = (39x1)/26

z = 1.5 moles

So, your answer would be that 1.5 moles of LiF would be equivalent to 39 grams.

Atomic mass of Li + Atomic mass of F

= 7 + 19

= 26

We can also say that one mole of LiF is equal to 26 grams.

Now, if 26 grams equal 1 mole, how many moles do 39 grams contain? Let's see:

z = (39x1)/26

z = 1.5 moles

So, your answer would be that 1.5 moles of LiF would be equivalent to 39 grams.