How many moles of h2so4 are required to
neutralize 4 litres 2N NAOH solution

4 moles of H2SO4 are required

Explanation:

The reaction of H2SO4 with NaOH is:

H2SO4 + 2 NaOH → 2H2O + Na2SO4

That means, 2 moles of sulfuric acid reacts per mole of NaOH.

The moles of NaOH in 4L of a 2N NaOH are:

2N NaOH = 2 M = 2 moles of NaOH per liter.

4 liters are:

4L * (2 moles NaOH / L) = 8 moles NaOH.

That means you need to add:

8 moles NaOH * (1 mole H2SO4 / 2 moles NaOH) =

8 m/s because for him to get the same amount of energy as ray is putting out, bobby, who weighs half as much as ray, needs to run twice as fast.