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 :
The constant used for the absorption of heat by the sample in melting is . Thus, option A is correct.
The chemical reaction has been defined as the energy in which the energy has been released or absorbed for the breaking of bonds in the reactants and the formation of product.
<h3>Constant for energy absorbed</h3>The energy has been absorbed in the melting of the copper sample. Thus, the sample has been converted from the solid to the liquid state.
The change in energy with the conversion in solid and liquid state has been termed as heat of fusion.
The energy has been absorbed by the system, thus it has been marked with the positive sign.
Therefore, has been the constant used for the absorption of heat by the sample in melting. Thus, option A is correct.
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