November 28, 2024, 01:53:23 AM
Forum Rules: Read This Before Posting


« previous next »
Pages: [1]   Go Down

Topic: stoichiometry problem  (Read 4835 times)

0 Members and 1 Guest are viewing this topic.

semistry

  • Guest
stoichiometry problem
« on: October 13, 2005, 07:53:39 PM »
hello, this problem is tough, and I did everything very carefully but it doesn't turn out correctly.


Iron (II) reacts with the dichromate ion in acidic solution rapidly and completely according to the following reaction:
14H+ (aq) + 6Fe2+ (aq) + Cr2O72- (aq) ===> 6Fe3+ (aq) + 2Cr3+ (aq) + 7H2O (l).  How many milliliters of 0.0124 M Cr2O72- are required to react with 0.742g of Fe(NH4)26H2O, a source of Fe2+ ion?

At one point I got 25.4 mL, and at another point I got 152.6 mL.
« Last Edit: October 13, 2005, 07:55:10 PM by semistry »
Logged

Offline constant thinker

  • mad scientist
  • Sr. Member
  • *****
  • Posts: 1275
  • Mole Snacks: +85/-45
  • Gender: Male
Re:stoichiometry problem
« Reply #1 on: October 13, 2005, 08:06:25 PM »
http://theodoregray.com/PeriodicTable/MSP/BalanceReactions

That website helps, but you should know how to do it. Do like I do: First I do the problem out. Then I check everything with that website.
Logged
"The nine most terrifying words in the English language are, 'I'm from the government and I'm here to help.' " -Ronald Reagan

"I'm for anything that gets you through the night, be it prayer, tranquilizers, or a bottle of Jack Daniels." -Frank Sinatra

Offline mike

  • Retired Staff
  • Sr. Member
  • *
  • Posts: 1245
  • Mole Snacks: +121/-35
  • Gender: Male
Re:stoichiometry problem
« Reply #2 on: October 13, 2005, 08:27:41 PM »
I get 49.9 mL (~50mL).
Logged
There is no science without fancy, and no art without facts.

semistry

  • Guest
Re:stoichiometry problem
« Reply #3 on: October 13, 2005, 11:46:40 PM »
hey mike that's not what i got though
Logged

Offline mike

  • Retired Staff
  • Sr. Member
  • *
  • Posts: 1245
  • Mole Snacks: +121/-35
  • Gender: Male
Re:stoichiometry problem
« Reply #4 on: October 13, 2005, 11:48:16 PM »
can you show your working?
Logged
There is no science without fancy, and no art without facts.

Offline xiankai

  • Chemist
  • Full Member
  • *
  • Posts: 785
  • Mole Snacks: +77/-37
  • Gender: Male
Re:stoichiometry problem
« Reply #5 on: October 14, 2005, 02:30:52 AM »
i got 49.8 mL, and i have no idea how u got 25 mL and 152 mL
Logged
one learns best by teaching
Pages: [1]   Go Up
« previous next »
Sponsored Links