[achibaby1974]

Ok. Online HW says

Calculate each of the following:

f.) mass in grams of .57 mol KMnO4
Okay so I start out with .57 mol.

.57 mol KMnO4 (158.04 g KMnO4/ 1 mol KMnO4) = 90.0828

I put 90 , 90.08 and 90.1 and they're all wrong. It says check significant figures. WHY? 

[Borek]

90 should be OK, no idea why it is rejected.