Calculate the number of atom in 4.90g of H₂SO₄ ?

To calculate it let us first write molar mass 

The molar mass of H₂SO₄ is 98.1 g/mole.

We are given the mass as 4.90g

So,  4.90g of H₂SO₄ is 

(4.90g)/(98.1 g/mole) = 0.050 moles

But we know that ,

1 mole = 6.022x10²³ atoms

Therefore in 0.05 moles the number of atom present can be found as,

(0.050moles) x ( 6.022x10²³ atoms/mole) = 3.01x10²² atoms

Hence we found that in 4.9g of H₂SO₄ we have 3.01x10²² atoms present