A 7.49g sample of compound of C, H, and O burns in presence of oxygen to produce 15.0g CO2 and 8.17g H2O. ?
What mass of Oxygen was present in original sample? What is this reaction equation?
Answer:- We Know mass of sample of compound = 7.49g,
15.0 g of CO2= 0.3409 M.
8.17g of H2O = 0.4534 M
I think the reaction is \(CH_2O(g) + O_2(g) \rightarrow CO_2(g) + H_2O(l) \)
Now, how to proceed further?
Finding out unknown moles and masses in the compound
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- Dhamnekar Winod
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Finding out unknown moles and masses in the compound
Any science consists of the following process. 1) See 2)Hear 3)Smell,if needed 4)Taste, if needed 5)Think 6)Understand 7)Inference 8)Take decision [Believe or disbelieve, useful or useless, true or false, cause or effect, any other criteria]
- ChenBeier
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Re: Finding out unknown moles and masses in the compound
Why do you think its the right equation. Show your calculation.
According to the moles of CO2 and H2O the ratio C: H has to be 4:10. In Formaldehyde it is 1:2. So this can not be right.
The mass difference gives 15 g O2 from outside. Its 0.5 mol.
According to the moles of CO2 and H2O the ratio C: H has to be 4:10. In Formaldehyde it is 1:2. So this can not be right.
The mass difference gives 15 g O2 from outside. Its 0.5 mol.
- Dhamnekar Winod
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Re: Finding out unknown moles and masses in the compound
How did you compute the molar ratio of C:H as 4: 10 according to moles of CO2 and H2O? I am not saying the reaction stated in my original thread is correct. I just expressed my opinion.In the original question reaction is not given. You said the stated reaction is wrong. I agree.
Chemistry Professor on other chemistry education site has given the following answer:
mass of compound = 7.49 g
mass of CO2 = 15.0 g
moles of CO2 = 0.3409 moles
moles of C = 0.3409 moles(How is this computed?)
mass of C = 4.0909 g
mass of H2O = 8.17 g
moles of H2O = 0.4535 moles
moles of H = 0.9070 (How is this computed?)
mass of H 0.9142
mass of C+H = 5.01 g
mass of O = 2.48 g
Chemistry Professor on other chemistry education site has given the following answer:
mass of compound = 7.49 g
mass of CO2 = 15.0 g
moles of CO2 = 0.3409 moles
moles of C = 0.3409 moles(How is this computed?)
mass of C = 4.0909 g
mass of H2O = 8.17 g
moles of H2O = 0.4535 moles
moles of H = 0.9070 (How is this computed?)
mass of H 0.9142
mass of C+H = 5.01 g
mass of O = 2.48 g
Any science consists of the following process. 1) See 2)Hear 3)Smell,if needed 4)Taste, if needed 5)Think 6)Understand 7)Inference 8)Take decision [Believe or disbelieve, useful or useless, true or false, cause or effect, any other criteria]
- ChenBeier
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Re: Finding out unknown moles and masses in the compound
You have 0.3409 mol of CO2 this is equal to the mole of C. Then you have 0.4535 mol of water this is equal to the double because water contain 2 H also 0.907 mol. That is what the proffessor also calculated.
So now you normilize these numbers. Set Carbon to 1 and divide the other. You get 2.66 for H. Now you multiply until the numbers almost not brocken. Multiply by 4 gives C 4 and H10.6 ~ 10, also C4H10
Then you do the same with the oxygen computed by the proffessor. You get almost 2.
So the formula is C4H10O2.
So now you normilize these numbers. Set Carbon to 1 and divide the other. You get 2.66 for H. Now you multiply until the numbers almost not brocken. Multiply by 4 gives C 4 and H10.6 ~ 10, also C4H10
Then you do the same with the oxygen computed by the proffessor. You get almost 2.
So the formula is C4H10O2.