[greenwoodturner]

First off, I have no chemistry background at all.  I am trying to help a friend in Romania, who is studying for the medical entrance exam.  I am researching the following problem, but just have not been able to understand what to do ... it seems it should be simple.  I had to translate the problem from Romanian to English, so hopefully it makes sense   Besides finding out the answer, I would love to understand what needed to be done to get the answer.  Thanks in advance!

Here is the question:

What is the molar ratio of CH4 : H2O after the conversion efficiency of 60%, if the initial ratio was 1:3?

[AWK]

This is not a big chemistry.
Just write down a conversion reaction with stoichiometric amount of water assuming a complete conversion.
Then take into account a given efficiency for this reaction.
In the next step add an excesing amount of water to both side of reaction.
And finally calculate ratio (unreacted methane from the left side and unreacted water from the right side of equation).

All can be done without calculator!

[greenwoodturner]

Thanks for the quick response!  I agree that it isn't big chemistry ... but it is big chemistry for a 60 year old who last looked at high school chemistry 40 years ago    I'm not completely sure that I understood your explanation ... but I will think about it for a while ... I may post another response asking for more help, if I can't figure it out

[greenwoodturner]

OK ... I'm stuck ... again

I assume that when you say to write down a conversion reaction with stoichiometric amount of water assuming a complete conversion, you mean the following:

CH4 + 2O2 -> C02 + 2H2O

But I'm not sure what you mean by taking into account the efficiency.

In the next step you talked about adding water to both sides of the reaction; since the problem states that the initial CH4:H2O ratio was 1:3, I assume that the formula becomes:

CH4 + 2O2 + 3H2O -> CO2 + 5H2O

And then I also didn't understand the last step ... sorry 

[AWK]

There is no information on the presence of oxygen in the reaction mixture.

[greenwoodturner]

I don't know what to say ... the full text of the question I'm trying to solve was provided in the initial post.  If something is missing, then I don't even know what to say 

[AWK]

You used word "conversion" - this means reaction in which the desired chemical(s) is (are) formed.
You write down reaction of combustion (wrongly balanced) in which heat is produced.
Meaning of conversion reaction may come from context in the texbook. My meaning is a production of "syngas" (synthesis gas) - a mixture od CO and H₂.
see:
https://en.wiki2.org/wiki/Methane+Newton => chemical feedstock
(Newton in this case means a new form of presentation in wikipedia, which I like)

[greenwoodturner]

This is one of those instances where I am in way over my head   Chemistry is not my strong suit at all.  I used the word "conversion" because that was one of the possible translations for the Romanian word "conversiei".  As I said before, I don't even understand the problem I am trying to solve ... I'm trying to help my adopted daughter in Romania.  What I really need is for someone to basically work through the problem so that I can understand it enough to explain to my daughter

[Arkcon]

after the conversion efficiency of 60%

The conversion rate for a currency is 1 to 2.  You have 100 currency, and you'll get 200 euros.  But they're going to take 40% away from you.   What do you get?

[AWK]

Write down reaction of methane conversion from wikipedia.
Then translate my instructions from my first post to your daughter (step by step).
She probably catch them.

[greenwoodturner]

Thank you for taking the time to respond.  Sadly, translating your instructions into Romanian will not help my daughter either.  She is trying really hard to study for the entrance exam into medical school.  She has a study guide of questions that they give to prepare for the exam, but her chemistry knowledge is not up to speed with respect to some of the questions in the study guide.  I volunteered to try to learn how to solve this problem, but I have failed ... it is beyond me.  I've been successful with other organic chemistry questions, but there are two which have stymied me ... and this is one of them.  Maybe I ventured into the wrong forum.  I figured that maybe I could find someone who was willing to walk me through the problem space, so that I could then explain it to my daughter.  Thank you for the attempts to lead me to the solution, but my mind is just way too tired anymore to be able to follow what you've shared 

[AWK]

CH₄ + H₂O = CO + 3H₂
Forget the excessing water at the moment. 60 % ot this reaction is:

Then add unreacted CH₄ (up to 1 mole) and water (up to 1 mole) on the both side or equation and add the excessive 2 moles of water also on both sides.

Calculate ratio of unreacted methane on the right side of equation to the whole unreacted water on the same side. Leave ratio as a simple fraction.

[greenwoodturner]

Thanks!  Was the 60% part missing from your response ... or am I still dense ... LOL   I didn't seem to see it in your post.

[AWK]

?

Forget the excessing water at the moment. 60 % ot this reaction is:

[greenwoodturner]

OK ... I give ... I still don't understand ... sorry for being dense ... thank you for being patient

I have since learned that there are 5 possible answers to this question ... yes, it was a multiple choice question, but I didn't know that 

The possible answers are:

a) 6:1
b) 3:1
c) 1:6
d) 1:1
e) remains the same

The only way I will ever understand this (so that I can explain it) is to be spoon-fed ... I need the steps completely spelled out ... assume you are talking to someone who knows almost nothing about chemistry   Thanks in advance