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How is hess law used to calculate the enthalpy change of reaction?
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What is one reason to use Hess's law?
Because enthalpy is a state function and an extensive property.
How is Hess's law used to measure enthalpy of a desire reaction?
... Intermediate equations with known enthalpies are added together.
How is hess law used to measure enthalpy of a desired reaction?
... Intermediate equations with known enthalpies are added together.
Why it is necessary to mention physical states of reactants and products in thermochemical reaction by hess's law?
Hess's law is important to thermochemistry because it allows us to anticipate enthalpy changes of reactions that are too slow to realistically record, such as rusting or reactions that are too fast. Hess's law, stating that the enthalpy is the same regardless of the pathway, allows us to take known enthalpy values and substituting them in to find your target reaction's enthalpy change. Credentials: I almost have a high-school diploma :P, so don't quote me; u won't sound any smarter than I do. S14 ftw!
What explains the entropy change of a gas reaction?
if there is an increase in the number of gas molecules , then ^S > 0
What is the Hess's law?
C - The enthalpy of reaction does not depend on the steps taken in the reaction. APEX --WXM--
Hess's law is based on what principle?
Hess's law is based on the principle that the enthalpy change of a reaction is independent of the pathway taken. This means that the overall enthalpy change for a reaction is the same, regardless of the number of steps involved in the reaction as long as the initial and final conditions are the same.
How is Hess's law applied in calculating enthalpy?
All the reactions in a path are added together.
Would the enthalpy change be different if solid sodium hydroxide pellets were added to hydrochloric acid instead of adding hydrochloric acid to sodium hydroxide solution?
Yes, the reaction involving the solid is actually an individual step in the equation of the reaction between the solutions. If you were to add the change in enthalpy of the reaction with the solid NaOh to the change in enthalpy of the other step in the reaction (that's adding water and the NaOh pellets) you would find the sum equivalent to the change in enthalpy of the reaction involving the two solutions (this is supported by Hess's law). I suggest that you consider Hess's law for more information.
What does Hess's law make it possible for you to do?
Hess's law makes it possible to determine the overall enthalpy change for a chemical reaction by combining the enthalpy changes of multiple indirect reactions that add up to the desired reaction. This allows the prediction and calculation of the energy changes in chemical reactions, even if direct measurement of the reaction is not possible.
How do you solve Hess's law problems?
To solve Hess's law problems, first write out the chemical equations for all reactions involved. Then calculate the enthalpy change for each reaction. Finally, add or subtract the enthalpy changes to obtain the overall enthalpy change for the desired reaction.
What is one reason to use Hess's law?
Because enthalpy is a state function and an extensive property.
How can an unknown H be determined using hess's law?
To use Hess Law, one simply uses the known equations and their respective ∆H values, rearranges them as necessary to arrive at the target equation (unknown ∆H) and then adds the ∆H values to obtain the value for the target equation. This is possible because Hess Law applies to state functions which are independent of the path.
If you need to multiply the reaction by 2 to be an intermediate reaction in a hess law problem what would be the final value for the enthalpy of reaction you use for this intermediate reaction?
-572k
If you multiply the following reaction by 2 to be an intermediate reaction in a Hess's law problem what would be the final value for the enthalpy of reaction you use for this intermediate reaction?
-572 k
What does Hess's law say about the enthalpy of a reaction?
The enthalpy of a reaction does not depend on the reactant path taken.
If you need to reverse the following reaction in order for it to be an intermediate reaction in a Hess's law problem what would be the final value for the enthalpy of reaction you use for this in?
1410 kJ
