April 28, 2024, 06:13:02 PM
Forum Rules: Read This Before Posting


Topic: Calculating volume of HNO3 necessary to neutralize?  (Read 3745 times)

0 Members and 1 Guest are viewing this topic.

Offline h20h

  • New Member
  • **
  • Posts: 8
  • Mole Snacks: +0/-0
Calculating volume of HNO3 necessary to neutralize?
« on: April 14, 2007, 12:59:21 AM »
Q:  Calculate the volume of 0.6M HNO3 necessary to neutralize 28.55 mL of 0.45M KOH?

My solution:  HNO3 + KOH = H20 + KNO3    (KNO3 is the neutral salt)
the stoich is 1:1:1:1, so I took the 28.55 mL of KOH and converted to L which came out to be .02855 liters of KOH.  I then took those liters and multiplied by .45M and divided by 1 liter to get .0128 moles KOH.  Since the stoich is 1:1  the moles of KOH is the same as the moles of HNO3.  So I took the 0.128 moles of HNO3 and divided by the .6M that was given in the question..since M equals # of moles/liter of solution I just rearranged that equation to solve for liters and the result is .0213 liters and then multiplied by 1000 to get 21.3mL?   

Any suggestions, help here?

Thanks

Offline Borek

  • Mr. pH
  • Administrator
  • Deity Member
  • *
  • Posts: 27665
  • Mole Snacks: +1801/-410
  • Gender: Male
  • I am known to be occasionally wrong.
    • Chembuddy
Re: Calculating volume of HNO3 necessary to neutralize?
« Reply #1 on: April 14, 2007, 12:05:05 PM »
I got 21.41 mL.
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Offline h20h

  • New Member
  • **
  • Posts: 8
  • Mole Snacks: +0/-0
Re: Calculating volume of HNO3 necessary to neutralize?
« Reply #2 on: April 14, 2007, 12:10:47 PM »
Did I do something wrong in the calculations? 

This is what I have:

28.55mL/1000mL  =  .02855 liters(.45M)/1liter =  .0128 moles of KOH

stoich 1:1

.0128 moles of HN03/.6M  =  .0123 liters(1000ml)  21.3 mL needed

am I off somewhere???

Thanks and let me know

Offline Borek

  • Mr. pH
  • Administrator
  • Deity Member
  • *
  • Posts: 27665
  • Mole Snacks: +1801/-410
  • Gender: Male
  • I am known to be occasionally wrong.
    • Chembuddy
Re: Calculating volume of HNO3 necessary to neutralize?
« Reply #3 on: April 14, 2007, 02:21:46 PM »
Don't round off intermediate results.
ChemBuddy chemical calculators - stoichiometry, pH, concentration, buffer preparation, titrations.info

Sponsored Links