Copyright ©
Houghton Mifflin Company. All rights reserved.
ANSWER
Choice 1 properly relates enthalpy to q. At constant pressure, any work
is change in volume work. So, DH
= DE + PDV and since q (at constant
pressure) = DE + PDV it follows that DH = q (at constant P where
most chemical reactions take place).
Section
6.3: Hess’s Law