- #1
Est120
- 51
- 3
why do we use the entalphy of formation of water at standard conditions to calculate the entalphy of a reaction even if water is not gas at 1bar and 298K
Est120 said:why do we use the entalphy of formation of water at standard conditions to calculate the entalphy of a reaction even if water is not gas at 1bar and 298K
The enthalpy of formation is the amount of energy released or absorbed when a substance is formed from its constituent elements in their standard states at standard conditions. It is a measure of the stability of a substance.
Water is used as the standard state for enthalpy of formation because it is the most abundant and stable compound on Earth. It also has a well-defined and easily reproducible standard state at standard conditions (25°C and 1 atm).
Standard conditions refer to a set of specific and well-defined conditions used for comparing and measuring physical and chemical properties of substances. These conditions include a temperature of 25°C and a pressure of 1 atm.
The enthalpy of formation of a substance is determined by measuring the heat released or absorbed during a chemical reaction in which the substance is formed from its constituent elements in their standard states at standard conditions. This is typically done using calorimetry.
The enthalpy of formation is important because it provides valuable information about the stability and energy content of a substance. It can also be used to calculate other thermodynamic properties, such as the enthalpy of reaction, which is useful in predicting the feasibility of a chemical reaction.