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Calculate the heat produced by the complete combustion of 50g of methanoic acid.

User Zerkz
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Step-by-step explanation:

To calculate the heat produced by the complete combustion of methanoic acid (also known as formic acid), we need to know its balanced chemical equation for combustion and the standard enthalpy of combustion (ΔH°) for the reaction.

The balanced chemical equation for the combustion of methanoic acid (HCOOH) is:

HCOOH + 1.5 O2 → CO2 + H2O

The stoichiometric coefficient for methanoic acid is 1, meaning 1 mole of HCOOH reacts with 1.5 moles of O2 to produce 1 mole of CO2 and 1 mole of H2O.

The standard enthalpy of combustion (ΔH°) for the reaction is -890 kJ/mol of HCOOH. This means that for every mole of methanoic acid that undergoes combustion, 890 kJ of heat is released.

To calculate the heat produced by the complete combustion of 50g of methanoic acid, we need to convert the mass of methanoic acid to moles and then use the molar enthalpy:

Step 1: Calculate the moles of methanoic acid (HCOOH) using its molar mass:

Molar mass of HCOOH = 12.01 (C) + 1.01 (H) + 16.00 (O) + 16.00 (O) = 60.02 g/mol

Moles of HCOOH = Mass of HCOOH / Molar mass of HCOOH

Moles of HCOOH = 50 g / 60.02 g/mol ≈ 0.833 moles

Step 2: Calculate the heat produced using the molar enthalpy of combustion:

Heat produced = Moles of HCOOH × ΔH° of combustion

Heat produced = 0.833 moles × -890 kJ/mol ≈ -742.37 kJ

The negative sign indicates that the reaction releases heat (exothermic), and the value of approximately 742.37 kJ represents the heat produced by the complete combustion of 50g of methanoic acid.

User Shahid Hamdam
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