-calculez masa de KOH din solutie;
C/100=md/ms--> 7/100= m,d/ 400---> m,d=28g KOH
Vm= 22,4l/mol
-din ecuatia reactiei se deduce:
1molSo2......2molKOH......1molK2so3
22,4l................................(2X39gK+32gS +3X16gO)/mol
5,6l...................................m=39,5g K2SO4
SAU 2X56gKOH..........158gK2SO3
28.....................m=39,5gK2SO4