Question

Decomposition of NI₃ produces nitrogen gas and iodine. How many grams of the reactant would be required to react completely to give 4.23 g of the iodine?

Answer 1

Ans :- 4.39 g

Explanation :-

Decomposition of NI₃ is :

2 NI₃ (s) --------------------> N₂ (g)............... +..................... 3 I₂ (g)

2 mol..................................1 mol.........................................3 mol

2 x 394.7 g/mol..............28 g/mol....................................3 x 253.8 g/mol

789.4 g...............................28 g...........................................761.4 g

From chemical equation it is cleared that

761.4 g of iodine is obtained from = 789.4 g of NI₃

So

4.23 g of iodine is obtained from = 789.4 g x 4.23 g / 761.4 of NI₃ = 4.39 g  of NI₃

Hence

Grams of the reactant would be required = 4.39 g