SO₂ Cl₂ on reaction with excess of water results into acidic mixture
SO₂ Cl₂+2 H₂ O → H₂ SO₄+2 HCl
16 moles of NaOH is required for the complete neutralisation of the resultant acidic mixture. The number of moles of SO₂ Cl₂ used is :

Solution

Chemistry ma’am · 3 steps

One SO₂Cl₂ makes three acids worth of H⁺: two from H₂SO₄ and one from each HCl.

1. Count the H+. 1 mol SO₂Cl₂ gives 1 mol H₂SO₄ and 2 mol HCl. H₂SO₄ is dibasic, so it supplies 2 mol H⁺, and the two HCl supply 2 more.
2. NaOH per mole. So 1 mol SO₂Cl₂ ends up as 4 mol of H⁺, and each H⁺ needs one OH⁻. That means 4 mol NaOH per mole of SO₂Cl₂.

   n_(SO₂Cl₂) = 16/4 = 4 mol

3. So. 4 mol of SO₂Cl₂ was used, which is option (c).

The idea to keep. In neutralisation, count replaceable H⁺, not molecules of acid. Add up the H⁺ from every acid formed, then match it one-to-one with OH⁻.

Answer from the NTA final answer key. Solution by PrepWiser.