March 28, 2024, 12:27:53 PM
Forum Rules: Read This Before Posting


Topic: going in circles when balancing equation  (Read 34431 times)

0 Members and 1 Guest are viewing this topic.

Offline Borek

  • Mr. pH
  • Administrator
  • Deity Member
  • *
  • Posts: 27637
  • Mole Snacks: +1799/-410
  • Gender: Male
  • I am known to be occasionally wrong.
    • Chembuddy
going in circles when balancing equation
« on: April 13, 2006, 11:15:50 AM »
I need an example of such situation - unfortunately whenever I try I am just balancing, can't locate a loop. I am just too good ;)
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Offline woelen

  • Chemist
  • Full Member
  • *
  • Posts: 277
  • Mole Snacks: +40/-2
  • Gender: Male
  • The art of wondering makes life worth living...
    • Science made alive
Re: going in circles when balancing equation
« Reply #1 on: April 13, 2006, 02:48:15 PM »
??  ???
Want to wonder? See http://www.oelen.net/science

Offline Borek

  • Mr. pH
  • Administrator
  • Deity Member
  • *
  • Posts: 27637
  • Mole Snacks: +1799/-410
  • Gender: Male
  • I am known to be occasionally wrong.
    • Chembuddy
Re: going in circles when balancing equation
« Reply #2 on: April 13, 2006, 02:56:57 PM »
When somebody not fluent in equation balancing starts to work on some 'complicated' case it sometimes end in a circle - "to balance A atoms I have to modify B coefficient, in turn there is not enough C atoms and I have to modify D coefficient - which makes my equation lacking A atoms which forces me to modify B coefficient" - and circle closes here.

I just have troubles constructing such example.
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Offline Albert

  • Lonely Wanderer
  • Retired Staff
  • Sr. Member
  • *
  • Posts: 1050
  • Mole Snacks: +112/-22
  • Gender: Male
  • Half Decent Pharmaceutical Chemist
Re: going in circles when balancing equation
« Reply #3 on: April 13, 2006, 03:16:23 PM »
Oh, I think I've got it! You want us to propose you such examples, don't you?

Offline Borek

  • Mr. pH
  • Administrator
  • Deity Member
  • *
  • Posts: 27637
  • Mole Snacks: +1799/-410
  • Gender: Male
  • I am known to be occasionally wrong.
    • Chembuddy
Re: going in circles when balancing equation
« Reply #4 on: April 13, 2006, 03:57:52 PM »
Yes. I have approached several equations trying to make this mistake but I am too efficient in NOT making it :)
« Last Edit: April 13, 2006, 04:01:58 PM by Borek »
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Offline woelen

  • Chemist
  • Full Member
  • *
  • Posts: 277
  • Mole Snacks: +40/-2
  • Gender: Male
  • The art of wondering makes life worth living...
    • Science made alive
Re: going in circles when balancing equation
« Reply #5 on: April 14, 2006, 04:12:41 AM »
Try this one. When working with the adjustment method, as you mentioned above, this one is hard:

CH3ONa + NaClO2 + HCl --> COCl2 + NaCl + H2O

Balancing by means of linear algebra methods is easy, but balancing by hand may be quite hard for a beginner.
Want to wonder? See http://www.oelen.net/science

Offline Borek

  • Mr. pH
  • Administrator
  • Deity Member
  • *
  • Posts: 27637
  • Mole Snacks: +1799/-410
  • Gender: Male
  • I am known to be occasionally wrong.
    • Chembuddy
Re: going in circles when balancing equation
« Reply #6 on: April 14, 2006, 04:20:32 AM »
Good one, thanks!
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Offline Borek

  • Mr. pH
  • Administrator
  • Deity Member
  • *
  • Posts: 27637
  • Mole Snacks: +1799/-410
  • Gender: Male
  • I am known to be occasionally wrong.
    • Chembuddy
Re: going in circles when balancing equation
« Reply #7 on: April 14, 2006, 02:03:09 PM »
I think I have found a better one - looks much simpler ot first sight:

P4O6 -> P4 + P2O4

but is surprisingly hard to balance by inspection.
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Offline Alberto_Kravina

  • Assault Chemist
  • Retired Staff
  • Full Member
  • *
  • Posts: 608
  • Mole Snacks: +70/-15
Re: going in circles when balancing equation
« Reply #8 on: April 14, 2006, 02:35:20 PM »
I balanced it (I don't post the reaction, I don't want to spoil it ;) ... the other members should try to balance it as well...)

KD00LS

  • Guest
Re: going in circles when balancing equation
« Reply #9 on: April 14, 2006, 04:38:46 PM »
I find it very easy to attempt to balance the molecules with the most amount of elements, then work down to the molecules with the least amount. That way, when you get down to balancing the last molecule, you won't disrupt any other pre-determined coefficients.

I also balanced this, took me under 30 seconds. ;D
« Last Edit: April 14, 2006, 04:45:52 PM by KD00LS »

Offline Borek

  • Mr. pH
  • Administrator
  • Deity Member
  • *
  • Posts: 27637
  • Mole Snacks: +1799/-410
  • Gender: Male
  • I am known to be occasionally wrong.
    • Chembuddy
Re: going in circles when balancing equation
« Reply #10 on: April 14, 2006, 05:25:46 PM »
This one will probably take you longer:

P2I4 + P4 + H2O -> PH4I + H3PO4
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Offline pantone159

  • Mole Herder
  • Chemist
  • Full Member
  • *
  • Posts: 492
  • Mole Snacks: +54/-6
  • Gender: Male
  • A mole of moles doesn't smell so nice...
    • Go Texas Soccer!!
Re: going in circles when balancing equation
« Reply #11 on: April 14, 2006, 07:48:31 PM »
Not so hard.  I is only on the right in 1 place, so is O, then after that H is only on the right in one unknown place, then you just have to count the P's.
Kind of ugly coeffients though.

KD00LS

  • Guest
Re: going in circles when balancing equation
« Reply #12 on: April 15, 2006, 02:28:36 AM »
I tried for about 10 minutes, I can't figure that last one out. I can't get the ratio of H to O on the product side to be 2:1 like it is on the reactant side.

Offline Mitch

  • General Chemist
  • Administrator
  • Sr. Member
  • *
  • Posts: 5298
  • Mole Snacks: +376/-3
  • Gender: Male
  • "I bring you peace." -Mr. Burns
    • Chemistry Blog
Re: going in circles when balancing equation
« Reply #13 on: April 15, 2006, 04:45:21 AM »
Check Jched, they love comparing methods for these types of things.
Most Common Suggestions I Make on the Forums.
1. Start by writing a balanced chemical equation.
2. Don't confuse thermodynamic stability with chemical reactivity.
3. Forum Supports LaTex

Offline Borek

  • Mr. pH
  • Administrator
  • Deity Member
  • *
  • Posts: 27637
  • Mole Snacks: +1799/-410
  • Gender: Male
  • I am known to be occasionally wrong.
    • Chembuddy
Re: going in circles when balancing equation
« Reply #14 on: April 15, 2006, 06:15:47 AM »
Many of these, although some not directly on the subject:

J.Chem.Educ. 22, 266, 461 (1945). 72, 716, 1125 (1995).
J.Chem.Educ. 36, 215 (1959). 74, 1359 (1997).
J.Chem.Educ. 38, 327 (1961). 65, 45 (1988). 74, 1270 (1997). 76, 362 (1999).
J.Chem.Educ. 69, 276 (1992)
J.Chem.Educ. 23, 550 (1946). 36, 77 (1959). 74, 69 (1987). 76, 362 (1999)
J.Chem.Educ. 38, 329 (1961). 74, 1365, 1365 (1997)
J.Chem.Educ. 62, 507 (1985). 72, 894 (1995).
J.Chem.Educ. 73, 507 (1996). 74, 1367, 1368 (1997).
J.Chem.Educ. 54, 704 (1977). 59, 728 (1982). 69, 279 (1992). 71, 295 (1994). 74, 1369 (1997).
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Sponsored Links