April 13, 2021, 03:25:25 AM
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### Topic: mixture  (Read 1031 times)

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#### inorganiic

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##### mixture
« on: March 25, 2021, 04:21:21 AM »
The mixture of hydrogen, methane and co gases under normal conditions has a density of 0.857g per dm3. 4.52 volumes of air are required for complete combustion of one volume of the mixture. Determine the composition of the mixture in percent. Can someone hel pe

#### sjb

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##### Re: mixture
« Reply #1 on: March 25, 2021, 05:05:08 AM »
Where have you got stuck? Can you, for instance, write individual equations for each of the reactions going on?

#### inorganiic

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##### Re: mixture
« Reply #2 on: March 25, 2021, 05:23:02 AM »
OK

#### inorganiic

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##### Re: mixture
« Reply #3 on: March 25, 2021, 05:30:30 AM »
Oh am i suposed to use 21 percent o2 in air?
CH4 + O2 ---> CO2 + 2H2O
2CO + O2 --->2CO2
2H2 + O2---> 2H2O

#### Borek

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##### Re: mixture
« Reply #4 on: March 25, 2021, 05:42:04 AM »
Oh am i suposed to use 21 percent o2 in air?

Yes.

Hint: you have to use information given to build a system of equations where your unknowns are percentages of gases in the mixture.
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#### inorganiic

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##### Re: mixture
« Reply #5 on: March 25, 2021, 05:57:41 AM »
Can i calculate V of O2 and make proportion for each reaction but actually i don`t know how to calculate this and what to use for 0.857 g per dm3
« Last Edit: March 25, 2021, 06:09:11 AM by inorganiic »

#### inorganiic

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##### mixture
« Reply #6 on: March 25, 2021, 08:11:19 AM »
sorry for posting here
The mixture of hydrogen, methane and co gases under normal conditions has a density of 0.857g per dm3. 4.52 volumes of air are required for complete combustion of one volume of the mixture. Determine the composition of the mixture in percent.
CH4 + O2 ---> CO2 + 2H2O
2CO + O2 --->2CO2
2H2 + O2---> 2H2O
can someone solve this, thank you so much

#### chenbeier

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##### Re: mixture
« Reply #7 on: March 25, 2021, 08:20:04 AM »
Burning of methane is wrong.

#### inorganiic

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##### Re: mixture
« Reply #8 on: March 25, 2021, 08:24:15 AM »
I know 2 before O2 but how to solve this

#### inorganiic

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##### mixture
« Reply #9 on: March 25, 2021, 09:49:51 AM »
sorry for posting here
The mixture of hydrogen, methane and co gases under normal conditions has a density of 0.857g per dm3. 4.52 volumes of air are required for complete combustion of one volume of the mixture. Determine the composition of the mixture in percent.
CH4 + 2O2 ---> CO2 + 2H2O
2CO + O2 --->2CO2
2H2 + O2---> 2H2O
can someone solve this, thank you so much

#### billnotgatez

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##### Re: mixture
« Reply #10 on: March 25, 2021, 10:24:04 AM »
@ inorganiic
We only post a given question once on the forum.
This is a forum policy.
Click on the link near the top center of the forum page.
Forum Rules: Read This Before Posting.
http://www.chemicalforums.com/index.php?topic=65859.0

I moved all your posts to here so as not to have duplicates

#### inorganiic

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##### Re: mixture
« Reply #11 on: March 25, 2021, 12:04:15 PM »
oh i didn't knew and i'm so sorry. Can you solve this problem or tell me how
« Last Edit: March 25, 2021, 03:02:22 PM by Borek »

#### Borek

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##### Re: mixture
« Reply #12 on: March 25, 2021, 03:04:16 PM »
Assume fraction of gases to be x, y, z. If these are fractions - what is their sum?

Assume there is 1L of the mixture - can you express its mass using x, y, z? how is it related to the mixture density?
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#### inorganiic

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##### Re: mixture
« Reply #13 on: March 25, 2021, 03:15:03 PM »
ok i calculated that the mass of the mixture is 0.857g but how to set up the system and what is the volume of air used for

#### inorganiic

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##### Re: mixture
« Reply #14 on: March 25, 2021, 03:47:05 PM »
can I solve without the system in some way and how to use the data of 4.52 air volume. does that mean 4.52 * 0.21 for each equation