Suppose reaction A involves the making of bonds and 225 J of ...

[ericka1]

Suppose reaction A involves the making of bonds and 225 J of energy, reaction B involves the breaking of bonds and 400 J of energy, and reaction C involves the making of bonds and 125 J of energy.
 
  What is the overall A + B + C reaction energy? Is this an exothermic or an endothermic reaction? Explain.

Question 2

The meaning of the word energy is immediately clear to anyone.
 
  What will be an ideal response?

[laurnthompson]

Answer to Question 1

In making bonds, the total energy release was 225 J + 125 J = 350 J. This is less
than the energy supplied to break bonds, 400 J. Overall in this reaction, bonds are broken
and net energy is supplied to the chemical system by the outside world. This is an
endothermic reaction, because energy in the amount of 50 J = 400 J - 350 J needs to be
added to the system for the reaction to occur.

Answer to Question 2

We wish I would hope the student will recognize from this opening chapter the
difficulty here.

[ericka1]

Excellent

[matt95]

Gracias!