Question

I posted this question already but you never replied back :(

Consider the following reaction at 298 K:
C(graphite) +2Cl2 (g) -----> CCl4(l)

Calculate the following quantities.

Delta H: -139 kJ/mol

deltaS(sys)=? J/mol*K
deltaS(surr)=? J/mol*K
deltaS(univ)=? J/mol*K


My answer is:
deltaS(sys)=-253.3J/mol*K
deltaS(surr)=466.4 J/mol*K
deltaS(univ)=231.4 J/mol*K

Delta (surr) and (univ) are correct. But delta (sys) is wrong...please help thanks!

chemistry - DrBob222, Friday, March 16, 2012 at 11:38pm

How did you calculate the dS sys? What values did you use?

chemistry - Leila, Saturday, March 17, 2012 at 2:40pm

Change in Hf(kJ/mol) Change in G Change in S

C(graphite) 0 0 5.7
Cl2 0 0 223.1
CCl4 -139 -68.6 214.4

Answer 1

************The values I used

C(graphite):
change in delta Hf=0
change in delta G= 0
change in delta S= 5.7

Cl2
change in delta Hf=0
change in delta G= 0
change in delta S= 223.1

CCl4
change in delta Hf=-139
change in delta G= -68.6
change in delta S= 214.4

Answer 2

The values above are in the units of kJ/mol

Answer 3

never mind I subtracted wrong the answer is -235.4 hahaha