Question

Calculate the standard enthalpy of formation of C2H6 from the following data : 2C2H6 + 7O2 = 4CO2 + 6H2O
∆H°= -3119kJ

Answer 1

Explanation:

Enthalpy change is the name given to the amount of heat evolved or absorbed in a reaction carried out at constant pressure. It is given the symbol ΔH, read as "delta H". Note: The term "enthalpy change" only applies to reactions done at constant pressure.

Enthalpy of Solution (Heat of Solution) Example

Calculate the heat released, q, in joules (J), by the reaction: q = mass(water) × specific heat capacity(water) × change in temperature(solution) ...

Calculate the moles of solute (NaOH(s)): moles = mass ÷ molar mass. ...

Calculate the enthalpy change, ΔH, in kJ mol-1 of solute:

Use the formula ∆H = m x s x ∆T to solve.

Once you have m, the mass of your reactants, s, the specific heat of your product, and ∆T, the temperature change from your reaction, you are prepared to find the enthalpy of reaction. Simply plug your values into the formula ∆H = m x s x ∆T and multiply to solve.Q = mc∆T. Q = heat energy (Joules, J) m = mass of a substance (kg) c = specific heat (units J/kg∙K) ∆ is a symbol meaning "the change in"