Question

To calculate the change in enthalpy, it is appropriate to use the equation: ΔH = Σ Reactants - Σ Products
True or False?

Answer 1

false. State functions like enthalpy, entropy, gibbs' and temperature chages, are always taken from the standpoint of (final state) - (initial state). The "final state" of a chemical reaction are the products, and the "initial state'" are the reactants, so that reverses the order of the Delta H
\[\Delta H = \Sigma \Delta H_{products} - \Sigma \Delta H_{reactants}\]

Answer 2

Thank You!

Answer 3

Could you help me with one more?

Why are heat transfers associated with phase changes known as latent or "hidden" heats?


A. Heat absorbed or released in a phase change is measured in kJ while temperature is measured in °C.

B. The enthalpy of vaporization and enthalpy of condensation values for a substance add to zero.

C. The enthalpy change values for pure substances tend to be small.

D. The heat absorbed or released by a phase change does not cause a temperature change.

Answer 4

this was asked a few weeks ago, let me see if i can find it

Answer 5

okay thank you

Answer 6

http://openstudy.com/users/jfraser#/updates/4f8ee14fe4b000310fad1b7f

Answer 7

Thanks so much!