Lets look at the numbers. 3X32. The first number is the power 3x will give you 3 times the closeup view. 32 represents how wide you see. 32mm. So a 3X32 will give you the same close up option as the 3X40 but a little less width than the 3X40. If this is what you want then the 3X32 is your choice. It's up to you.
1x96 2x48 3x32 4x24 6x16 8x12
That will depend upon personal requirements. Both have 3 power magnification. The second number is the diameter of the ocular. The larger the number the more light gathering power and the larger field of view the scope will have.
Al2(SO3)3 has r.f.m.= (2x27 + 3x32 + 9x16) = 294 Thus 25 g is 25/294 = 0.085 moles of aluminium sulfite. We have 0.085 moles in 175 ml of solution, which would be 0.085 x 1000/175 moles in a litre = 0.486 M