Question

Which statement best describes how energy can change during a chemical reaction?

A. The energy change for a chemical reaction can either be exothermic (it gives off heat) or endothermic (it requires heat to proceed).
B. The energy change for a chemical reaction can either be exothermic (a positive enthalpy) or endothermic (a negative enthalpy).
C. The energy change of a chemical reaction is always zero, from the first law of thermodynamics.
D. The energy change for a chemical reaction can either be endothermic (it gives off heat) or exothermic (it requires heat to proceed).

Answer 1

exothermic - heat is produced
Endothermic - heat is consumed

Answer 2

So the answer is D?

Answer 3

nan read that again

Answer 4

oh oops it's A right?

Answer 5

i think so