Question

what is the color of the residue formed when Feso4 is heated

Answer 1

FeSO4 is a  crystal which contains water in the form of water of  crystallisation. So FeSO4​ is actually represented as FeSO4 . 7 H2O , which means that it contains 7 water molecules . The water molecules give  FeSO4 its pale green colour .
When it  is heated, ​FeSO4 . 7 H2O loses  the water through evapouration and changes its colour from pale green to colourless. 
When further heated ​, FeSO4 decomposes  to form ferric oxide and sulphur dioxide and ​sulphur trioxide.
FeSO4 (s)       --->    ​Fe2O3 (s)     +  SO2  (g) +  SO4 (g)
(pale green)            (brown)    

Answer 2

___hello friend___

hope the answer will help you

when heating ferrous sulphate crystal lose water and annhydrous ferrous sulphate Feso4
is formed and there colour changes from light green too white



hope the answer will help you!!!!