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  1. #1
    Crushing souls Hickeydog's Avatar
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    Need chemistry help

    geeze. this chemistry stuff is like the english language: more exceptions than rules. Anyways..

    A 27.0 g sample of ethylene glycol, a car radiator coolant, loses 690. J of heat. What was the initial temperature of ethylene glycol if the final temperature is 32.5C? (c of ethylene glycol = 2.42 J/gK)

    So. The formula is J=(c)(mass)(change in T). So I solved for Ti and came up with Ti=Tf-J/(c)(mass). And I came up with 21.9 degrees centigrade for the answer. Only problem is, this answer is wrong.

    Help. me. Please.
    Quote Originally Posted by Wordbiker View Post

    What's frightening is how coherent Hickey was in posting that.

  2. #2
    Hazardous Taerom's Avatar
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    Help me, jschen Kenobi. You're my only hope.

  3. #3
    enginerd jeff^d's Avatar
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    You have the change in T correct, but think about the question. If it loses heat, should the initial temperature be higher or lower than the final temperature?

  4. #4
    Rawwrrrrrrrrr! wolfpack's Avatar
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    do you have a selection of answers?
    wolfpackcycles
    skiffrun: Enjoy the ride. Ride for the enjoyment.

  5. #5
    Hazardous Taerom's Avatar
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    42

  6. #6
    Crushing souls Hickeydog's Avatar
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    No selection of answers. And I tried + and -. both are wrong.
    Quote Originally Posted by Wordbiker View Post

    What's frightening is how coherent Hickey was in posting that.

  7. #7
    Crushing souls Hickeydog's Avatar
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    Quote Originally Posted by Taerom View Post
    42
    42. what? I need that decimal..
    Quote Originally Posted by Wordbiker View Post

    What's frightening is how coherent Hickey was in posting that.

  8. #8
    Rawwrrrrrrrrr! wolfpack's Avatar
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    42 is the answer to everything....ohh boy...you've a lot to learn and i've alot to teach.

    < snaps fingers > now get back to working on that chemistry!!
    wolfpackcycles
    skiffrun: Enjoy the ride. Ride for the enjoyment.

  9. #9
    Crushing souls Hickeydog's Avatar
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    yeah. I entered in the 42 and I got within 10% of the correct answer. So 29.1 is definitely out. And I think it's positive.
    Quote Originally Posted by Wordbiker View Post

    What's frightening is how coherent Hickey was in posting that.

  10. #10
    enginerd jeff^d's Avatar
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    I said you already have the change in temperature correct. Just go the other way.

    It's 32.5 plus the difference between 32.5 and your 21.9 answer. I feel...wrong...just giving it to you.

  11. #11
    Crushing souls Hickeydog's Avatar
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    never mind. I figured it out.

    GOD I FLIPPING HATE CHEMISTRY!!!!! GGGGGGGGGGAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHHHH!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    Quote Originally Posted by Wordbiker View Post

    What's frightening is how coherent Hickey was in posting that.

  12. #12
    Crushing souls Hickeydog's Avatar
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    Quote Originally Posted by jeff^d View Post
    I said you already have the change in temperature correct. Just go the other way.

    It's 32.5 plus the difference between 32.5 and your 21.9 answer. I feel...wrong...just giving it to you.
    And giving the answer to me would be like giving a crippled guy (such as my proffessor soon-to-be) a wheelchair.
    Quote Originally Posted by Wordbiker View Post

    What's frightening is how coherent Hickey was in posting that.

  13. #13
    GATC
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    43.06

  14. #14
    GATC
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    This is algebra, not chemistry. It's all about the units/labels.

  15. #15
    Rawwrrrrrrrrr! wolfpack's Avatar
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    yea...how dang hard was it to get 43.06. that's waht i got too.
    wolfpackcycles
    skiffrun: Enjoy the ride. Ride for the enjoyment.

  16. #16
    Senior Member deraltekluge's Avatar
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    Quote Originally Posted by Hickeydog View Post
    never mind. I figured it out.

    GOD I FLIPPING HATE CHEMISTRY!!!!! GGGGGGGGGGAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHHHH!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    But this really isn't a chemistry problem. It's just a very simple algebra problem, and it is stated more in terms of physics than chemistry, anyway.

  17. #17
    riding once again jschen's Avatar
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    Quote Originally Posted by Taerom View Post
    Help me, jschen Kenobi. You're my only hope.
    People who want help should show their work and explain all their reasoning. And try not to post questions the day after jschen had a long night. But then, who knew that I would end up spending 6 hours at a bar on a Thursday night when I went alone just to grab a quick dinner?
    If you notice this notice then you will notice that this notice is not worth noticing.

  18. #18
    You Know!? For Kids! jsharr's Avatar
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    I knew. I called ahead and told the bartender you were coming in.
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    Quote Originally Posted by colorider View Post
    Phobias are for irrational fears. Fear of junk ripping badgers is perfectly rational. Those things are nasty.

  19. #19
    riding once again jschen's Avatar
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    No wonder they didn't seem shocked!
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