106. Solving a chemistry problem

56. Calculate the reaction rate of Na2S2O3 H2SO4 → Na2SO4 SO2 H2O S in a solution with initial concentrations of Na2S2O3 and H2SO4 equal to 0.05 mol/l and C(H2SO4)=0.04 mol/l, respectively, at the moment when the concentration of Na2S2O3 decreased by 2 times. The reaction rate constant is 0.05 l/s (the reaction is 1 order in Na2S2O3 concentration and 0 order in H2SO4 concentration).