how much heat is liberated by the combustion of 206 grams of hydrogen?
ΔHcomb= -286kj/mol
A sample of ammonia liberates 5.66 kJ of heat as it solidifies at its melting point
To calculate the amount of heat liberated by the combustion of 206 grams of hydrogen, we need to follow these steps:
Step 1: Calculate the number of moles of hydrogen
To find the number of moles, we can use the molar mass of hydrogen, which is approximately 1 gram/mol.
Number of moles = Mass of hydrogen / Molar mass of hydrogen
Moles = 206 g / 1 g/mol
Moles = 206 mol
Step 2: Calculate the heat liberated
The given value, ΔHcomb = -286 kJ/mol, represents the enthalpy change for the combustion of 1 mole of hydrogen.
Heat liberated = ΔHcomb x Number of moles
Heat liberated = -286 kJ/mol x 206 mol
Heat liberated = -58916 kJ
Therefore, the combustion of 206 grams of hydrogen liberates approximately 58,916 kJ of heat.
To find the amount of heat liberated by the combustion of 206 grams of hydrogen, you can use the molar mass of hydrogen (1 gram/mole) and the given enthalpy change of combustion (ΔHcomb = -286 kJ/mol). Here's how you can calculate it:
Step 1: Convert the mass of hydrogen to moles.
Number of moles of hydrogen = Mass of hydrogen (g) / Molar mass of hydrogen (g/mol)
In this case, Mass of hydrogen = 206 grams and Molar mass of hydrogen = 1 gram/mol.
Hence, Number of moles of hydrogen = 206 g / 1 g/mol = 206 moles.
Step 2: Calculate the amount of heat liberated.
Amount of heat liberated = Number of moles of hydrogen × ΔHcomb
In this case, Number of moles of hydrogen = 206 moles and ΔHcomb = -286 kJ/mol.
Hence, Amount of heat liberated = 206 moles × -286 kJ/mol = -58,916 kJ.
Therefore, the combustion of 206 grams of hydrogen would liberate approximately -58,916 kJ of heat. The negative sign indicates that it is an exothermic reaction, meaning heat is released.
2H2 + O2 ==> 2H2O
286 kJ/mol x (1 mol H2/2 g H2) = 143 kJ/gram hydrogen.
So 206 g Hydrogen x (143 kJ/g) = ?? kJ.
Check my thinking.