Calculate the volume of concentrated (98% v.v) H2SO4 that you will need to prepare 250ml of an 5.4 M H2SO4 solution.Density of 98% v.v H2SO4 = 1.84 g/cm3

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I am having difficulty understanding the problem and units. The concentration of H2SO4 is 98% (v/v). Surely not. I suspect that is 98% w/w. That makes sense. 98% v/v means 98 mL pure H2SO4/100 mL H2SO4 solution. I've never seen 100% H2SO4 although it can be made by infusing 98% w/w H2SO4 with gaseous SO3 to make fuming H2SO4. Nor do I understand the statement that 98% v/v H2SO4 has a density of 1.84 g/cc. It's my understanding that 98% w/w H2SO4 has a density of 1.84 g/cc.
If you mean 98% w/w having a density of 1.84 g/cc then the problem is worked this way.
1.84 g/cc x 1000 cc x 0.98 x (1/98) = 18.4 M for that solution. Then if you wish to prepare 250 mL of a 5.4 M solution, use the dilution formula of
mL1 x M1 = mL2 x M2
mL1 x 18.4 = 250 mL x 5.4M. Solve for mL1, pipet that volume of the 98% stuff into a 250 mL volumetric flask holding about 125 or so mL distilled H2O, let cool, make to the mark with distilled water, stopper, mix thoroughly,, label. Done.