Thursday
August 28, 2014

Homework Help: chemistry

Posted by Anonymous on Sunday, November 16, 2008 at 3:42am.

Label each of the following reactions as exothermic or endothermic ("exo" or "endo"), and according to whether work is done on or by the system ("on" or "by")? Note that no "en-on" cases appear here, as these are always thermodynamically unfavourable. There is no need to do any calculation, use chemical arguments to predict the sign of the enthalpy change.


3 NaN3(s) --> Na3N(s) + 4 N2(g)
(Simplified version of the chemical reaction in air bags. NaN3 is sodium azide.)

2 Cl(g) --> Cl2(g) H2O(l) --> H2O(g)

2 Li(s) + H2O(l) --> 2 LiOH(aq) + H2(g)

H2(g) + O2(g) --> 2 H2O(l)

i would say that all of them are exothermic except for the last one...is that right?

but i dont know how to find out whether work is done on or by the system.

Answer this Question

First Name:
School Subject:
Answer:

Related Questions

Chemistry - Label each of the following reactions as exothermic or endothermic...
chemistry URGENT (2) - Label each of the following reactions as exothermic or ...
Chemistry!! - Could anyone name the enthalpy change by name AND if it is ...
Chemistry - I'm having a hard time understanding Endothermic and Exothermic ...
Chemistry - When given a chemical reaction, how would I know whether a reaction ...
Chemistry - Predict whether the following reactions will be exothermic or ...
chemistry - following equilibrium system with a Kc of 1.23E-03: C3H6O (aq) + ...
environmental chemistry - Are these endothermic or exothermic? A) cracking large...
chemistry(please check) - Just made it a new post didnt what it to get ...
Chemistry - H2 and F2 react according to the following equation, forming HF. H2(...

Search
Members