What's the difference between magnesium sulfate anhydrous and magnesium sulfate heptahydrate

1. The content of magnesium is different
The content of magnesium in magnesium sulfate heptahydrate is different from that in magnesium sulfate anhydrous. The content of magnesium in magnesium sulfate anhydrous is 1.78 times that in magnesium sulfate heptahydrate.

2.  Appearance
The appearance of magnesium sulfate heptahydrate is a white powder, while magnesium sulfate heptahydrate is a transparent columnar colloid.

Crystal water
Magnesium sulfate anhydrous contains no crystal water and its relative molecular weight is 128, while magnesium sulfate heptahydrate contains crystal water and its relative molecular weight is 246.