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Question
What are the various ways in which a chemical equation can be made more informative? Give examples to illustrate your answer.
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Solution
The various ways in which a chemical equation can be made more informative are:
- By indicating the physical states of the reactants and products.
Example: Gaseous state is indicated by the symbol (g).
\[\ce{Zn_{(s)} + H2SO4_{(aq)} -> ZnSO4_{(aq)} + H2_{(g)}}\] - By indicating the heat changes taking place in the reaction.
Example: An exothermic reaction is indicated by writing +Heat, or +Heat energy, or +Energy on the products side of an equation.
\[\ce{C_{(s)} + O2_{(g)} -> Co_{(g)} + Heat}\] - By indicating the conditions under which the reaction takes place.
Example: Delta (Δ) stands for heat, which is written over the arrow of the equation.
\[\ce{2KClO3_{(s)} ->[\Delta][MnO2] 2KCl_{(s)} + 3O2_{(g)}}\]
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