The correct option is B 7.61 M
Assuming V mL of H2SO4 is mixed together.
For 30% (w/w) solution:
30% (w/w) means 30 g of solute is present in 100 g of the solution
Since, density of solution = mass of the solutionvolume of the solution
Mass of H2SO4 solution = 1.218 ×V = 1.218V g
100 g of the solution contains 30 g of H2SO4
1.218V g of the solution will contain = 30100×1.218V = 0.3654V g...(i)
Similarly,
70% (w/w) means 70 g of solute is present in 100 g of the solution
Since, density of solution = mass of the solutionvolume of the solution
Mass of H2SO4 solution = 1.610 ×V = 1.610V g
100 g of the solution contains 70 g of H2SO4
1.610V g of the solution will contain = 70100×1.610V = 1.127V g...(ii)
Total mass of the solute = 0.3654V + 1.127V = 1.4924V g
Moles of H2SO4 = given massmolar mass=1.4924V98 mol
Total volume of the solution = 2V mL = 2V1000 L
Molarity = moles of solutevolume of solution in L
Molarity = 1.4924V/982V/1000 = 7.61 M