March 29, 2024, 01:34:01 AM
Forum Rules: Read This Before Posting


Topic: HELP ASAP! OXIDATION NUMBERS QUESTION  (Read 5002 times)

0 Members and 1 Guest are viewing this topic.

Offline stevo312

  • Very New Member
  • *
  • Posts: 2
  • Mole Snacks: +0/-0
HELP ASAP! OXIDATION NUMBERS QUESTION
« on: May 19, 2008, 11:42:01 AM »
3.6g of magnesium metal were added to an excess of solution of an arsenic compound containing Asn+ and 7.5g of arsenic were deposited. what is the oxidation number of arsenic in the coumpound?
A. +2
B. +3
C. +4
D. +5

answer is +3 btw  but i need help to work it out

Offline Borek

  • Mr. pH
  • Administrator
  • Deity Member
  • *
  • Posts: 27633
  • Mole Snacks: +1799/-410
  • Gender: Male
  • I am known to be occasionally wrong.
    • Chembuddy
Re: HELP ASAP! OXIDATION NUMBERS QUESTION
« Reply #1 on: May 19, 2008, 12:40:04 PM »
Please write balanced reaction equation.
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Offline stevo312

  • Very New Member
  • *
  • Posts: 2
  • Mole Snacks: +0/-0
Re: HELP ASAP! OXIDATION NUMBERS QUESTION
« Reply #2 on: May 20, 2008, 04:54:31 AM »
there is no balanced equation, thats why i cant work it out

Offline Borek

  • Mr. pH
  • Administrator
  • Deity Member
  • *
  • Posts: 27633
  • Mole Snacks: +1799/-410
  • Gender: Male
  • I am known to be occasionally wrong.
    • Chembuddy
Re: HELP ASAP! OXIDATION NUMBERS QUESTION
« Reply #3 on: May 20, 2008, 05:15:29 AM »
No no no, it is up to YOU to write this equation. Note: try to write it using not some number (like 2, 3, 4) but using n (like in Asn+).
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Offline wilson

  • Regular Member
  • ***
  • Posts: 51
  • Mole Snacks: +0/-0
  • Gender: Male
Re: HELP ASAP! OXIDATION NUMBERS QUESTION
« Reply #4 on: May 20, 2008, 06:14:49 AM »
Yep, you can use A B C D to represent your stoichiometric coefficients. From there form a simple equation, to ensure that charges on both sides are balanced (this equation should contain n). And how to obtain the values of A B C D? Basic stoichiometry calculations from weight and molar mass.  :)

Sponsored Links