Go Back   Chemistry Help Forum > Chemistry Forums > Advanced Chemistry Forum

Advanced Chemistry Forum Organic chemistry, analytical chemistry, inorganic chemistry, physical chemistry, and biological chemistry questions go here.

Reply
 
Thread Tools Display Modes
Old Jul 7th 2014, 07:04 AM   #1
siewlyn
Junior Member
 
Join Date: Dec 2013
Posts: 20
siewlyn is on a distinguished road
dALTON LAW

mixture of gases contains 16g oxygen , 14 g of nitrogen and 22g carbon dioxide. the mixture is collected above water at a temperature 25 Celsius. the total pressure is 1 atm and vapor pressure is 40 torr at 25 Celsius. what is the partial pressure of carbon dioxide?
my work :
mole of oxygen = 0.5 mole
mole of nitrogen = 0.5 mole
mole of Carbon dioxide = 0.5 mole
mole fraction = number of moles CO2/ total no. of moles of gases
0.5/1.5= 0.33
total pressure is 1 atm= 760 torr
water pressure is 40 torr
thus, 760 torr - 40 torr = 720 torr
partial pressure CO2 = total pressure * mole fraction of co2
PP co2 = 720 * 0.33= 240 TORR


WHY ??? ANSWER IS 480 TORR

PLEASE HELP !! THANKS YOU SO MUCH AND GOD BLESS YOU ;P
siewlyn is offline   Reply With Quote
Old Jul 8th 2014, 05:33 AM   #2
bjhopper
Senior Member
 
Join Date: May 2010
Posts: 491
bjhopper is on a distinguished road
Dalton Law

Vapor pressure of water at 25 C= 23.76 mm Hg.If the total pressure is 760 mmHg then the other gasesi have partial pressure of 736.24 mm Hg.CO2 is I/3 of that or 245.4 mmHg.One mmHg =one Torr
bjhopper is offline   Reply With Quote
Old Jul 8th 2014, 06:25 PM   #3
siewlyn
Junior Member
 
Join Date: Dec 2013
Posts: 20
siewlyn is on a distinguished road
hi thanks do much !!
siewlyn is offline   Reply With Quote
Old Jul 8th 2014, 06:28 PM   #4
siewlyn
Junior Member
 
Join Date: Dec 2013
Posts: 20
siewlyn is on a distinguished road
hi i have another question... PLease help
which of the following solution is the most concentrated?
a. 1 M NACL
b. 1 m NACL
c. 55 g Of NACL mixed with 1 litre of water


1 M means 58.5g NACL in 1 L NACL right ?
what's 1m means?
why is the answer c but not A?
siewlyn is offline   Reply With Quote
Reply

  Chemistry Help Forum > Chemistry Forums > Advanced Chemistry Forum



Thread Tools
Display Modes



Facebook Twitter Google+ RSS Feed