Chapter U4.72, Problem 2E

Interpretation Introduction

Interpretation:

The difference in the coefficients in chemical equations and the subscripts in chemical formulas must be explained.

Concept introduction:

The coefficients in chemical equations describe the mole ratio in which the reaction is taking place and in which mole ratio products are generated. Subscripts in chemical formula describe the number of each atom present in that molecule.

Answer to Problem 2E

Coefficients in chemical equations represent the mole of the compound whereas the subscripts in chemical formulas represent number of atoms of the element present in one mole of the compound.

Explanation of Solution

A balanced chemical reaction between Al and H₂SO₄ is shown below.

  $2Al+3H_{2}S{O}_4\to A{l}_2{\left(S{O}_4\right)}_3+3H_2$

In this reaction coefficients of Al, H₂SO₄, Al₂(SO₄)₃ and H₂ are 2, 3, 1 and 3 respectively.

The coefficients of Al and H₂SO₄ are 2 and 3 respectively which states that 2 moles of Al reacted with 3 moles of H₂SO₄. But subscripts of H and O in H₂SO₄ are 2 and 4 respectively which states that there are 2 and 4 H and O atom respectively in 1 mole of H₂SO₄.