Question

Compound A is a colourless, crystalline, hydrated salt of magnesium. On hearing it becomes
an anhydrous salt. The number of water molecules lost by compound A is equal to number of water molecules present in green vitriol on heating.

i) Identify compound A.

ii) Give the Chemical equation for this heating reaction.​

Answer 1

Compound A is Epsom salt or Magnesium Sulphate heptahydrate (MgSO4.7H2O)

- Green Vitriol is the compound of iron denoted by the formula FeSO4·7H2O

- It is clear that it has 7 molecules of water.

- So, the given magnesium salt A loses 7 water of crystallisation on heating.

- The colourless crystalline magnesium salt with 7 water of crystallisation is Epsom Salt.