Cramster.com - Homework Solutions, Lecture Notes, Exams, and Free Online Homework Help
Sign Up Now! Login Customer Support
McAfee Secure sites help keep you safe from identity theft, credit card fraud, spyware, spam, viruses and online scams
Problem Solved.
    Home    
    Homework Help    
   Answer Board   
    Resources (Beta)    
   
You Are Here: Home > Answer Board > Chemistry > Topic: Calculate Rate Constant
Member's Topic Headline:

Calculate Rate Constant

Know the answer? Have a better solution? Share it.
Get Help Now.
View homework problems
explained for free!
Member Testimonials

Question:

Advertisement:
Answer | Ask New Question | Customize Profile | Leaderboards | 
FAQ

Member's Avatar
Scholar
Karma Points: 200
(Weber State University)
Respect (75%):
Date Posted: 6/29/2008 12:34:41 AM  Status: Closed
Calculate Rate Constant
Course Textbook Chapter Problem
General Chemistry N/A N/A N/A
Question Details:
For the gas-phase decomposition of hydrogen iodide:
 
2HI  H2 + I2
 
the rate constant, at 283 degrees C is 3.52 x 10-7 /M-sec. The activation energy for the reaction is 187 kJ/mole. Calculate the rate constant at 293 degrees C.
 
Answer: 7.18 x 10-7 /M-sec.
 
I have probably tried this problem six or seven times, so please show step by step instructions so I can find my error. Thank you so much!
Bonus Point Alert! Earn +4 additional karma points for helping this annual member.

Answers:

Member's Avatar
Sage
Karma Points: 3,963
Date Posted: 6/29/2008 9:26:46 PM  Status: Live
Asker's Rating: Lifesaver   
Response:
by arrhenius equation the rate constant is related to the temperatures as
 ln (k2/k1) = (E/R) [(1/T1)-(1/T2)]
where , E= activation energy= 187KJ/mol= 187x103J/mol
 R= gas constant= 8.314J/mol.K
T1= 2830C= 283+273=556K, k1= 3.52x10-7M-1s-1
T2= 2930C= 293+273=566K, k2 =?
ln (k2/k1) = ( (187x103J/mol)/( 8.314J/mol.K) )[(1/556K)-(1/566K)]
ln (k2/k1) =0.715
k2= 2.044* 3.52x10-7M-1s-1= 7.19x10-7M-1s-1
DragonCommand15's Comment:
Thanks so much!



By reading or posting messages on these forums, you are agreeing to the Answer Board's Terms of Service and Conduct (TSC).


About Cramster | Terms of Use | Privacy Policy | Contact Us | Press Room | Site Map | Support | Anti-Cheating Policy

Cramster.com is not affiliated with any publisher. Book covers, title and author names appear for reference only.
Copyright © 2008 Cramster, Inc.