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Find the enthalpy of combustion of ethanol given that

mass of ethanol burned = 1.65g,
mass of copper calorimeter = 295g
Mass of copper calorimeter= 500g
Initial temperature of water = 17.4°C
Rise in temperature of water= 19.9°C
Specific heat capacities of water is 4.2J/g/K; Copper is 2.1J/g/K

User Thiagoh
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1 Answer

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To calculate the enthalpy of combustion of ethanol, use the equation Enthalpy change = mass of water x specific heat capacity of water x temperature change. Plugging in the given values, the enthalpy of combustion per mole of ethanol is 466,480J/mol.

To calculate the enthalpy of combustion of ethanol, we can use the equation:

Enthalpy change = mass of water x specific heat capacity of water x temperature change

In this case, the mass of water is 200g, the specific heat capacity of water is 4.2J/g/K, and the temperature change is 19.9°C. Plugging these values into the equation, we get:

Enthalpy change = 200g x 4.2J/g/K x 19.9°C = 16716J

Since 1 mole of ethanol has a molar mass of 46.07g, we can calculate the enthalpy of combustion per mole using the mass of ethanol burned:

Enthalpy of combustion per mole = Enthalpy change / moles of ethanol

moles of ethanol = mass of ethanol burned / molar mass of ethanol

= 1.65g / 46.07g/mol = 0.0358 mol

Enthalpy of combustion per mole = 16716J / 0.0358 mol

= 466,480J/mol.

User Whitequill Riclo
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