Question

Number of H in 3(NH4)2Cro4

Answer 1

The number of H atoms in 3(NH₄)₂CrO₄ = 24

Further explanation  

The empirical formula is the smallest comparison of atoms of compound forming elements.  

A molecular formula is a formula that shows the number of atomic elements that make up a compound.  

(empirical formula) n = molecular formula  

Subscripts in the chemical formula indicate the number of atoms

The compound of 3(NH₄)₂CrO₄ ( 3 molecules of (NH₄)₂CrO₄ ) :

Number of H :

$\tt 4\times 2(subscript)\times 3(coefficient,number~of~molecules)=24~atoms$