Do Hess's Law equations have to be balanced

[kenshi64]

1. Research Question: How effectively can experimental values estimate the heat of hydration of Copper (II) Sulfate as compared to theoretical values found using Hess’s law?



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3. In the image above I have ΔH20 and ΔHreaction(not labelled) and intend to experimentally find out ΔH.
Problem: is that my textbooks states that equation can be used for Hess's Law if they're balanced. Are the equations in the image balanced? IMHO they're incomplete. That's my first problem, How can (aq) and (.5H20) be balanced?I prepared 0.025 solutions of both hydrated and anhydrous CuSO4 and measure their temperatures during hydration and forming of an aqueous solution respectively. IS that right?

Thank you for your interest! :D

 

[Nino MMP]

In order to answer your question, it is important to understand the concept of Hess’s Law. Hess’s Law states that the enthalpy change for a reaction can be determined by summing the enthalpy changes for each individual reaction step in the overall reaction. In other words, the enthalpy change for a reaction is equal to the sum of the enthalpy changes for the individual reaction steps. This means that you can use experimental values to estimate the heat of hydration of Copper (II) Sulfate as long as all the individual reaction steps are known. In the image above, the equations are incomplete. The equation for the hydration of Copper (II) Sulfate should be written as CuSO4 (aq) + 0.5 H2O (l) --> CuSO4.5H2O (aq). Once the equations are balanced, then you can measure the temperatures during hydration and forming of an aqueous solution of Copper (II) Sulfate. By comparing the experimental values with the theoretical values found using Hess’s Law, you can then evaluate how effectively experimental values can estimate the heat of hydration of Copper (II) Sulfate.