Question

What is formula unit mass and how is it determined?Calculate the formula mass of a compound
NA2S2O3

Answer 1

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Answer 2

hi

It is the sum of the atomic masses of all the atoms present in the formula unit of that compound. It is calculated in the same manner as that of molecular mass. The only difference is that we use formula unit mass for those substances whose constituent particles are ions.

FORMULA UNIT MASS OF Na2S2O3:-

= 2*(at. mass of Na) + 2*(at. mass of S) + 3*(At. mass of oxygen)

= 2*23 + 2*32 + 3*16

=158u