A sample of gas contains 0.1900 mol of CH4(g) and 0.3800 mol of O2(g) and occupi

Chemistry
Tutor: None Selected Time limit: 1 Day

A sample of gas contains 0.1900 mol of CH4(g) and 0.3800 mol of O2(g) and occupies a volume of 30.6 L. The following reaction takes place:


CH4(g) + 2O2(g)CO2(g) + 2H2O(g)

Calculate the volume of the sample after the reaction takes place, assuming that the temperature and the pressure remain constant.
May 28th, 2015

(no. of moles)/Volume = (no. of moles at S.T.P.)/(Volume at S.T.P.) 

(.1900+.3800)/30.6=(n)(v)......................................................

May 28th, 2015

whats the answer?

May 28th, 2015

whats the answer?

May 28th, 2015

(.5700)/30.6=(2)v

ans=47.5

May 28th, 2015

Avogadro's Law says that equal volumes of gases at the same temperature and pressure contain the same number of molecules (or moles). Mathematically this means that at a given temperature and pressure, the volume of a gas sample is directly proportional to the number of moles of gas in the sample:

V = constant  n

or

V1  =  V2  = constant
n1n2


From the stoichiometry of the balanced equation, it can be seen that the0.1900 mol CH4(g) and the 0.3800 mol O2(g) are present in amounts that react completely:

CH4(g) + 2O2(g)CO2(g) + 2H2O(g)

0.1900 mol CH4(g) [img src="http://cxp.cengage.com/contentservice/assets/T=1432666732132/owms01h/mediaarchives/GenChem/Image/times14-3.gif"> 2 mol O2(g)  =  0.3800 mol O2(g)
1 mol CH4(g)


Similarly, the balanced equation shows the amounts of products that form:

0.1900 mol CH4(g) [img src="http://cxp.cengage.com/contentservice/assets/T=1432666732132/owms01h/mediaarchives/GenChem/Image/times14-3.gif"> 1 mol CO2(g)  =  0.1900 mol CO2(g)
1 mol CH4(g)


0.1900 mol CH4(g) [img src="http://cxp.cengage.com/contentservice/assets/T=1432666732132/owms01h/mediaarchives/GenChem/Image/times14-3.gif"> 2 mol H2O(g)  =  0.3800 mol H2O(g)
1 mol CH4(g)


The intial and final volumes are directly proportional to the numbers of moles:

n1 = 0.1900 mol + 0.3800 mol = 0.5700 mol
V1 = 30.6 L  
n2 = 0.1900 mol + 0.3800 mol = 0.5700 mol
V2 = ? 

V2 =  V1[img src="http://cxp.cengage.com/contentservice/assets/T=1432666732132/owms01h/mediaarchives/GenChem/Image/times14-3.gif"> n2(30.6 L)(0.5700 mol)  = 30.6 L
n10.5700 mol

May 28th, 2015

it was 30.6 !

May 28th, 2015

Are you studying on the go? Check out our FREE app and post questions on the fly!
Download on the
App Store
...
May 28th, 2015
...
May 28th, 2015
Dec 8th, 2016
check_circle
Mark as Final Answer
check_circle
Unmark as Final Answer
check_circle
Final Answer

Secure Information

Content will be erased after question is completed.

check_circle
Final Answer