When a reaction takes place at constant pressure, the heat transferred is equal to the Question 2 options:

A)

energy of reaction.

B)

enthalpy of reaction.

C)

mass of reaction.

D)

entropy of reaction.

At constant pressure, the heat of reaction is equal to the enthalpy change of the system. Most chemical reactions occur at constant pressure, so enthalpy is more often used to measure heats of reaction than internal energy

the mantle

explanation:

earth is divided into three layers: the crust or the outermost layer on which we live; the underlying, middle layer - the mantle - and the core (the innermost layer of earth).

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