The enthalpy at constant pressure is given by which of the following?

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The definition of enthalpy at constant pressure is fundamentally tied to the relationship between heat transfer in a system and its state functions. Enthalpy, denoted by H, is defined as the sum of the internal energy U and the product of pressure (p) and volume (V). This is expressed mathematically as H = U + pV.

When considering changes in enthalpy with respect to temperature at constant pressure, the term C_p represents the heat capacity at constant pressure, which is defined as the change in enthalpy per unit change in temperature. This relationship, (∂H/∂T)_p, indicates how the enthalpy changes as temperature changes while pressure remains constant. Thus, it directly describes the thermodynamic behavior of the system under constant pressure conditions.

The statement that ΔH = q_p also points to a critical aspect of enthalpy, as it states that the change in enthalpy (ΔH) is equal to the heat absorbed or released at constant pressure (q_p). However, the question specifically asks about how enthalpy itself is defined and characterized at constant pressure, which aligns more closely with the relationship defined by the heat capacity, C_p.

Hence, defining enthal

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