Find the number of molecule(s) which on complete hydrolysis produces sulphuric acid as one of the product ${\mathrm{SOF}}_4,{\mathrm{SF}}_4,{\mathrm{H}}_2{\mathrm{S}}_2{\mathrm{O}}_8,{\mathrm{H}}_2{\mathrm{S}}_2{\mathrm{O}}_7,{\mathrm{SO}}_2{\mathrm{Cl}}_2,{\mathrm{S}}_3{\mathrm{O}}_9$

From the given options,${\mathrm{S}}_3{\mathrm{O}}_9$ on complete hydrolysis does not produces Sulphur acid by product. Apart from this rest 5 molecules produces Sulphur acid as one product.

Here, the molecules which on complete hydrolysis produces sulphuric acid as one of the product,

${\mathrm{SOF}}_4,{\mathrm{H}}_2{\mathrm{S}}_2{\mathrm{O}}_8,{\mathrm{H}}_2{\mathrm{S}}_2{\mathrm{O}}_7,{\mathrm{SO}}_2{\mathrm{Cl}}_2,{\mathrm{S}}_3{\mathrm{O}}_9$

 Thus, the correct answer is 5.