How many hydrogen atoms are in 4.40 mol of ammonium sulfide

The molecular formula for ammonium sulfide would be (NH4)2S. That means in one molecule of ammonium sulfide there will be 1 N + 4 H + 2 S molecules. 
Then the amount of hydrogen atoms in 4.4 moles of ammonium sulfide should be: 4.4 moles * 4/1= 17.6 moles 
If you are asked for atom count then the amount should be: 17.6 moles * 6.022x10^23 atoms/mol = 105.9872 * 10^23= 1.06 * 10^25

 The number  of hydrogen  atoms  that are  in 4.40  mol  of ammonium sulfide is  2.12 x10^25  atoms

      calculation
 find the number of moles  of Hydrogen  in ammonium sulfide  (NH4)2S

that is  4.40  x  number of hydrogen atoms in (NH4)2S ( 4x2= 8  atoms)

moles is  therefore=  4.40  x8= 35.2  moles

by  use of  Avogadro's law  constant

that is  1mole =  6.02 x10^23 atoms
         35.2  moles=?

by  cross multiplication
  {35.2 moles x 6.02 x10^23} /1 mole  = 2.12  x10^25  atoms

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