How many moles are present in 110 grams of lif? show your work in the space below
a. 4.2
b. 5.2
c. 2.1
d. 8.4

Answer choice A.

Explanation:

Li has an atomic mass of 6.941. F has an atomic mass of 18.998. Combine these to get 25.939 amu/grams. Take the 110 and divide it by 25.939 to get about 4.2. Hope this helps :)

One equation for the number of moles  in a compound:

(note: Mr is the combined molecular mass of the compound.)

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On the periodic table:

Lithium (Li) has a molecular mass of around 7

Fluorine (F) has a molecular mass of around 19.

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So the total Mr of Lithium Fluoride (LiF) is:

7 + 19 = 26

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Now to work out the number of moles, we just divide the mass (in grams) of the compound by the Mr of the compound (as in the formula):

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A) 4.2

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