Calculate the delta S rxn at 25 degrees celsius for the reaction 2NH3(g)-N2H4(g) + H2(g). Do you know where I can find these values of the S for these compounds?

Question

Calculate the delta S rxn at 25 degrees celsius for the reaction 2NH3(g)->>N2H4(g) + H2(g). Do you know where I can find these values of the S for these compounds?

aaronq · Answer

your textbook should have them, if not here http://www.mrbigler.com/misc/energy-of-formation.PDF

anonymous · Answer

Ok, yeah I searched it and found it online but I got an incorrect answer on Mastering Chemistry

aaronq · Answer

what formula did you use?

anonymous · Answer

delta S= H of (N2H4) + H of ( H2) - [2( H of NH3)]

aaronq · Answer

you're measuring entropy, not enthalpy. Use the S values not H.

$\Delta S= S^o_{N_2H_4} + S^o _{H_2} - [2( S^o_{NH_3})]$

anonymous · Answer

okay thank you very much