« previous next »
Pages: [1]   Go Down

Author Topic: chemistry  (Read 5725 times)

Offline CMayor

  • Newbie
  • *
  • Posts: 35
  • Reputation: 75
  • Gender: Male
  • BABA bless all :)
chemistry
« on: April 20, 2011, 05:38:13 am »
 N2O4 is a poisonous gas. It can be disposed of safely by reaction with sodium hydroxide.
N2O4(g) + 2NaOH(aq) ? NaNO3(aq) + NaNO2(aq) + H2O(l)
What is the minimum volume of 0.5 mol dm–3 NaOH(aq) needed to dispose of 0.02 mol of N2O4?
A 8 cm3 B 12.5 cm3 C 40 cm3 D 80 cm

PLEASE HELP
Logged

Offline NotAbod

  • Wikipedia Contributor
  • Global Moderator
  • SF Farseer
  • *****
  • Posts: 3929
  • Reputation: 65535
  • Gender: Male
Re: chemistry
« Reply #1 on: April 20, 2011, 09:16:39 am »
N2O4 + 2NaOH
u need to dispose 0.02 mol N2O4
use mole ratio to find moles of sodium hydroxide:
   1N2O4   +   2NaOh
      0.2              x
cross multiply, u need 0.04mol sodium hyrdoxide to dispose 0.02mol N2O4.
calculate the volume of NaOH needed using the formula :  moles / concentration
volume= 0.04/ 0.5(given in the question) = 0.08 dm3
to conver dm3 to cm3 multiply by 1000,
0.08 x 1000= 80 cm3, answer D


check attachments on the next post
« Last Edit: April 20, 2011, 09:38:58 am by AboD »
Logged

Offline NotAbod

  • Wikipedia Contributor
  • Global Moderator
  • SF Farseer
  • *****
  • Posts: 3929
  • Reputation: 65535
  • Gender: Male
Re: chemistry
« Reply #2 on: April 20, 2011, 09:37:24 am »
solved in a better way  ;)
Logged
Pages: [1]   Go Up
« previous next »