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NEETChemistryThermodynamics (C)

How can you calculate the enthalpy change for a reaction when you cannot measure it directly?

Options

  1. ABy using the ideal gas law
  2. BBy conducting experiments with different reactant concentrations
  3. CBy applying Hess's Law and finding related reactions with known enthalpy changes
  4. DBy using the heat capacity of the reactants

Correct answer

C. By applying Hess's Law and finding related reactions with known enthalpy changes

Step-by-step solution

When you cannot measure the enthalpy change for a reaction directly, you can calculate it by applying Hess's Law and finding related reactions with known enthalpy changes. This allows you to determine the enthalpy change for the desired reaction by combining the known reactions in a way that cancels out intermediate species.

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