the molarity of 2% by weight of aqueous solution of H2S4(molecular weight = 98)

Answer 1

2% w/w means 2g H2SO4/100 g soln or 20g/1000g solution.
20g is how many mols? That's 20/molar mass = ?
M = mols/L solution. You don't know the volume of the solution. You need the density to determine that.
volume = mass/density converted to L. Then M = mols/L will give it to you

Answer 2

100%=98g/mol=1mol
2%=X mol
Therefore
X=(2×1)÷100
X=0.02

Answer 3

Thanks a lot

Answer 4

chemistry