The number of H atoms in 3(NH₄)₂CrO₄ = 24
<h3>Further explanation </h3>
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 :
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The reducing agent is donating electrons and therefore becoming oxidised itself. In this scenario elemental zinc (Zn) is in a reduced state and is oxidised to become Zn2+, in doing so it donates electrons to Fe2+, thereby reducing it to elemental iron (Fe).
The elemental Zinc in solid state is therefore the reducing agent as it reduces Fe2+ to Fe(s).
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