Which statement is FALSE? a. ΔHrxn is the heat of reaction. b. ΔErxn is a measure of heat. c. An exothermic reaction gives heat off heat to the surroundings. d. Endothermic has a positive ΔH. e. Enthalpy is the sum of a system's internal energy and the product of pressure and volume.

a. ΔHrxn is the heat of reaction. TRUE. ΔHrxn or change in enthalpy of reaction is per definition the change in heat that is involved in a chemical reaction.

b. ΔErxn is a measure of heat. FALSE. Is the change in internal energy of a reaction

c. An exothermic reaction gives heat off heat to the surroundings. TRUE. An exothermic reaction is a chemical reaction that releases heat.

d. Endothermic has a positive ΔH. TRUE. When a process is exothermic ΔH<0 and when the process is endothermic ΔH>0

e. Enthalpy is the sum of a system's internal energy and the product of pressure and volume. TRUE. Under constant pressure and volume the formula is ΔH = ΔE + PV

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