Which of the following best explains why the enthalpy changes measured for a sequence…
CHEMISTRY · Single correct · A Level · Chemistry · Energetics · Energetics
Problem
Which of the following best explains why the enthalpy changes measured for a sequence of individual reactions can be summed to obtain the enthalpy change for an overall reaction?
(a) Because energy is conserved, the heat released or absorbed in each individual step must be identical, so summing the identical values gives the overall enthalpy change
(b) Because enthalpy is an extensive property proportional to the amount of substance, so values from different reactions can be directly added together
(c) Because enthalpy is a state function that depends only on the initial and final states of the system
(d) Because the sum of the bond energies broken always exactly equals the sum of the bond energies formed, making any sequence of steps energetically equivalent