Results 1 to 1 of 1

Thread: Chemistry problems...really need help!

  1. #1 Chemistry problems...really need help! 
    New Member
    Join Date
    Jan 2007
    When a 2.000 gram sample of pure phenol, C6H5OH(s), is completely burned according to the equation below, 65.98 kj of heat is released.

    a. Calculate the molar heat of combustion of phenol in kj/mol at 25 degrees Celsius.

    [6(213.6)+3(69.91)]-[(144.0)+7(205.0)] =
    = [1401.33]-[1579] = -87.67 kj/mol

    * I used delta G formula --> [products - reactants] and I know I'm not doing it right, yet I'm not sure what I am doing wrong. I don't know if I would use a regular proportion to figure this problem out of a formula. O_O

    Four bottles, labeled A through D, each containing about 5 grams of a finely powerded white substance are found in a lab. Near the bottles are four labels specifying high purity and indicating that the subst. are C6H12O6 (glucose), sodum chloride (NaCL), aluminum oxide (Al2O3), and (ZnSO4). sulfate. The labels belong to the bottles and have one substance. Describe the tests you would use to help find which label belongs to what bottle.

    *How would I figure out what label goes on what bottle? I'm REALLY confused on how to figure how which label goes on what, and which substance is actually in each bottle. Please help!!


    THANK YOU SO MUCH![img][/img]

    Reply With Quote  


Posting Permissions
  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts