One gram of calcium combines with 4 g of bromine while 1 g of hydrogen combines with 80 g of bromine. Calculate the equivalent weight of calcium. (at. wt. of Br= 80).

(i) wt. of H2=1g; wt. of Br2=80gWe know:                  wt. of bromine  wt. of H2= Eq. wt. of bromine  Eq. wt. of H2(=1.008)∴ Eq. wt. of bromine = wt. of bromine ×1.008 wt. of H2=80×1.0081=80.64. (ii)  wt. of Ca wt. of bromine = Eq. wt. of Ca Eq. wt. of bromine (=80.64)∴ Eq. wt. of Ca= wt. of Ca wt. of bromine ×80.64=1×80.644=20.16 Ans.