Which of the following is potash alum?
Na2SOβAlβ(SOβ)β·24HβO
KβSOβAlβ(SO4)β·24HβO
KβSOβAlβ(SOβ)β·12HβO
NaβSOβAlβ(SOβ)β·20HβO
B. KβSOβAlβ(SO4)β·24HβO