Homework problem E.21

[Katie Frei 1L]

Hello! For part b) of problem E.21 in the 7th edition of the textbook, both of my answers for the amount of moles and molecules of HF included four significant figures because the problem initially gave the mass of HF to be 25.92 mg. However, in the solutions manual, the final answers for part b) are given using three significant figures. Does anyone know why this is the case? Thanks!

[Veronica Soliman 4H]

I don't have this directly in front of me, however, as a general rule of thumb, look in the question itself for the number with the least sig figs reflect that in your answer.