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A 1.50 g sample of hydrocarbon (containing C & H only) undergoes complete combustion to produce 4.40 g of CO2 and 2.70 g of H2O. Calculate the empirical formula of the compound.

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Answer:

Step-by-step explanation:

To find the empirical formula of the hydrocarbon, we need to determine the relative amounts of carbon and hydrogen in the compound. We can do this by using the masses of CO2 and H2O produced during combustion.

First, let's calculate the moles of CO2 and H2O produced:

moles of CO2 = 4.40 g / 44.01 g/mol = 0.100 mol

moles of H2O = 2.70 g / 18.02 g/mol = 0.150 mol

Next, let's determine the number of moles of carbon and hydrogen in the hydrocarbon. During combustion, the hydrocarbon reacts with oxygen to produce CO2 and H2O. The balanced chemical equation for the combustion of a hydrocarbon can be written as:

CnHm + (n + m/4)O2 → nCO2 + m/2H2O

where n and m are the coefficients that balance the equation.

From the equation, we can see that for every n moles of CO2 produced, there must be n moles of carbon in the original hydrocarbon. Similarly, for every m/2 moles of H2O produced, there must be m/2 moles of hydrogen in the original hydrocarbon.

Using this information, we can calculate the number of moles of carbon and hydrogen in the hydrocarbon:

moles of carbon = 0.100 mol

moles of hydrogen = 0.150 mol * 2 = 0.300 mol

Now, we need to find the empirical formula of the hydrocarbon by dividing the number of moles of each element by the smallest number of moles:

empirical formula CnHm = C(0.100 mol / 0.100 mol)H(0.300 mol / 0.100 mol) = CH3

Therefore, the empirical formula of the hydrocarbon is CH3.

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