I'll assume you mean sulfuric acid..
We're asked to find the number of #"H"# atoms there are in #36.0# #"g H"_2"SO"_4#.
To do this, let's first use the molar mass of sulfuric acid (#98.078# #"g/mol"#) to find the number of moles of #"H"_2"SO"_4#:
#36.0cancel("g H"_2"SO"_4)((1color(white)(l)"mol H"_2"SO"_4)/(98.078cancel("g H"_2"SO"_4))) = ul(0.367color(white)(l)"mol H"_2"SO"_4#
Now, we can use Avogadro's number to find the number of molecules of #"H"_2"SO"_4#:
#0.367cancel("mol H"_2"SO"_4)((6.022xx10^23color(white)(l)"molecules H"_2"SO"_4)/(1cancel("mol H"_2"SO"_4)))#
#= ul(2.21xx10^23color(white)(l)"molecules H"_2"SO"_4#
Finally, we realize that there are #2# atoms of hydrogen per molecule of sulfuric acid:
#2.21xx10^23cancel("molecules H"_2"SO"_4)((2color(white)(l)"atoms H")/(1cancel("molecule H"_2"SO"_4)))#
#= color(red)(ul(4.42xx10^23color(white)(l)"atoms H"#
