Question

4 g of a metallic chloride contains 1.89 g of the metal X. Calculate the empirical formula of the
thetallic chloride. (At. wt. of X = 64, Cl = 35.5]
​

Answer 1

step 1: find no of moles.

1 mole=at.weight of substance

i) 1 mol of x=64g

We wants for 1.89g,

÷64 on both sides, 1/64 mol=64/64 g

×1.89 on both sides, 1.89/64 mol=1.89g

therefore, 1.89g of X= 0.029 mol ≈0.03 mol

ii)1mol of cl2 = 2×35.5 g=71 g

÷71 and then ×4

4 g cl2=4/71= 0.056 mol ≈0.06 mol

step 2: find simple while no. ratio

for X. it is 0.03

for cl2 it is 0.06

therefore simple ratio is0.03/0.03 :0.06/0.03

=0.01 : 0.02

=1 : 2

therefore, empirical formula is X1 (Cl2)2