A compound containing only carbon, hydrogen and oxygen is subjected to elemental analysis. Upon complete combustion, a .1804g sample of the compound produced .3051g of CO2 and .1249g of H2O. What is the empirical formula of the compound?

Someone else did a problem just like it, and here is his setup; I just changed the numbers, and you should check my numbers

mass of C in sample = mass of C in CO2
mass of C in sample = (0.3051 g CO2 / 44 g/mol)(1 mol C / 1 mol CO2)(12 g/mol) = 0.08321 g

mass of H in sample = mass of H in H2O
mass of H in sample = (0.1249 g H2O / 18 g/mol)(2 mol H / 1 mol H2O)(1 g/mol) = 0.01388 g

mass of O in sample = total mass of sample - mass of C - mass of H
mass of O in sample = 0.1804 g - 0.08321 g - 0.01388 g = 0.08691 g
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Calculate for moles of C, H & O from the calculated masses:

moles of C = 0.08321 g/ 12 g/mol = 0.006934 mol
moles of H = 0.01388 g / 1 g/mol = 0.01388 mol
moles of O = 0.08691 g / 16 g/mol = 0.005432 mol
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Divide this moles with the lowest value which is 0.006934 mol

C = 0.006934/0.006934 = 1.00
H = 0.01388/0.006934= 2.00
O = 0.005432/0.006934= 0.783
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Multiply by 4 to make the ratios a whole number:

C = 1 x 4 = 4
H = 2 x 4 = 8
O = 0.783 x 4=3.13=3

Empirical Formula is C4H8O3

No. That is wrong. The lowest value that you should divided is 0.005432 mol. Then you can get:

C = 0.006934/0.005432 = 1.3
H = 0.01388/0.005432 = 2.6
O = 0.005432/0.005432 = 1

C = 1.3 x 3 = 3.9 ~ 4
H = 2.6 x 3 = 7.8 ~ 8
O = 1 x 3 = 3

Only then the Empirical Formula is C4H8O3

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Well, it seems we have quite the fiery situation here! Let's break down this combustion extravaganza.

We have a .1804g sample of the compound that produced .3051g of CO2 and .1249g of H2O. From these results, we can determine the amount of carbon and hydrogen present in the compound.

To calculate the amount of carbon, we know that 1 mole of CO2 contains 1 mole of carbon. So, using the molar mass of CO2 (44.01 g/mol), we can determine the moles of carbon in the CO2 produced:

moles of carbon = mass of CO2 / molar mass of CO2
= .3051g / 44.01 g/mol

Similarly, to calculate the amount of hydrogen, we know that 1 mole of H2O contains 2 moles of hydrogen. So, using the molar mass of H2O (18.02 g/mol), we can determine the moles of hydrogen in the H2O produced:

moles of hydrogen = mass of H2O / molar mass of H2O
= .1249g / 18.02 g/mol

Now, once the moles of carbon and hydrogen are determined, we need to find the moles of oxygen. Since the compound contains only carbon, hydrogen, and oxygen, we can use the principle of conservation of mass to find the moles of oxygen:

moles of oxygen = moles of carbon + moles of hydrogen - 1
= (moles of carbon) + (moles of hydrogen) - 1

Now that we have the moles of each element, we can find the ratio of atoms present. We divide each moles value by the smallest one to get a simple whole number ratio. Then, we can convert this ratio into empirical formula.

Well, enough of this number crunching circus act! Based on the calculations, the empirical formula of the compound is now ready to perform its grand reveal. Drumroll, please... The empirical formula of the compound is C1H2O1, which can be simplified to CH2O.

Voila! We have successfully determined the empirical formula of the compound, which appears to be CH2O. Keep in mind, my dear friend, that this is only the empirical formula. For the true molecular formula, we would need the molar mass of the compound.

So, it seems we have tamed the combustion chaos and found the empirical formula of the compound. I hope you enjoyed this fiery chemistry spectacle!

To determine the empirical formula of the compound, we need to find the ratio of the elements present in the compound.

The given information tells us that the compound contains carbon, hydrogen, and oxygen.

To begin, let's find the number of moles of CO2 and H2O produced.

1. Calculate the number of moles of CO2:
- The molar mass of CO2 is 44.01 g/mol (carbon: 12.01 g/mol, oxygen: 2 × 16.00 g/mol). Therefore,
moles of CO2 = mass of CO2 / molar mass of CO2
= 0.3051 g / 44.01 g/mol

2. Calculate the number of moles of H2O:
- The molar mass of H2O is 18.02 g/mol (hydrogen: 2 × 1.01 g/mol, oxygen: 16.00 g/mol). Therefore,
moles of H2O = mass of H2O / molar mass of H2O
= 0.1249 g / 18.02 g/mol

Next, we need to find the ratio of moles between carbon, hydrogen, and oxygen in the compound. Divide the number of moles of each element by the smallest number of moles calculated.

3. Find the moles of carbon:
Divide the moles of CO2 by its coefficient of carbon (1 mole of CO2 contains 1 mole of carbon):
moles of carbon = moles of CO2

4. Find the moles of hydrogen:
Divide the moles of H2O by its coefficient of hydrogen (1 mole of H2O contains 2 moles of hydrogen):
moles of hydrogen = 2 × moles of H2O

5. Find the moles of oxygen:
Subtract the total moles of carbon and hydrogen from the total moles of the compound:
moles of oxygen = total moles of the compound - moles of carbon - moles of hydrogen

Now we can determine the ratio of the elements by dividing each element's moles by the smallest number of moles calculated.

6. Divide the moles of each element by the smallest number of moles:
- Divide the moles of carbon, hydrogen, and oxygen by the smallest value among them.
- Round off the ratios obtained to the nearest whole number.
- If necessary, multiply the ratios by the smallest integer needed to make all the values whole numbers.

Finally, use the obtained ratio of elements to write the empirical formula of the compound.

For example, if the ratio of moles is carbon (C): 1, hydrogen (H): 2, oxygen (O): 1, the empirical formula would be CH2O.