an unknown gaseous hydrocarbon reacts with oxygen to form CO2 and H2O, DETERMINE HEAT OF FORMATION FOR THE HYDROCARBON. the density of the mixture of CO2 and H2O at 1 atm and 200 degree celsius is 0.751g /L and heat of reaction is equal to -2044.5 KJ /MOL hydrocarbon

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To determine the heat of formation for the hydrocarbon, we need to know the molar ratio between the hydrocarbon and the products formed (CO2 and H2O) in the reaction.

The balanced equation for the reaction is:
CnHm + (n + m/4)O2 -> nCO2 + m/2H2O

From the equation, we can see that for each mole of hydrocarbon that reacts, n moles of CO2 and m/2 moles of H2O are formed.

Given that the heat of reaction (-2044.5 KJ/mol of hydrocarbon) is the heat released when 1 mole of hydrocarbon reacts, we can use this information to calculate the heat of formation for the hydrocarbon.

First, we need to determine the number of moles of CO2 and H2O formed when 1 mole of hydrocarbon reacts. We can do this by comparing the balanced equation to the molar ratio.

Since n moles of CO2 and m/2 moles of H2O are formed for each mole of hydrocarbon, we can set up the following ratios:

n mol CO2 / 1 mol hydrocarbon = n mol CO2 / 1 mol CO2
m/2 mol H2O / 1 mol hydrocarbon = m/2 mol H2O / 1 mol H2O

By substituting the values from the equation, we get:

n mol CO2 / 1 mol hydrocarbon = 1 mol CO2 / 1 mol CO2
m/2 mol H2O / 1 mol hydrocarbon = 1 mol H2O / 1 mol H2O

Therefore, n moles of CO2 and m/2 moles of H2O are formed when 1 mole of hydrocarbon reacts.

Now, we can calculate the heat of formation for the hydrocarbon using the heat of reaction and the number of moles of CO2 and H2O formed.

Heat of formation of hydrocarbon = Heat of reaction / moles of hydrocarbon reacted

Heat of formation of hydrocarbon = -2044.5 KJ/mol / 1 mol

So, the heat of formation for the hydrocarbon is -2044.5 KJ/mol.