why is da value of heat of neutralization of NaOH AND HF is higher dan that of its constant value??
da?
dan?
If you want to be taken seriously here, you need to write/type in standard English please.
What do mean by "its constant value?
The heat of neutralization is, by definition, whatever it is.
The heat of neutralization is a measure of the amount of heat released or absorbed during a neutralization reaction, where an acid and a base react to form a salt and water. The value of the heat of neutralization for a specific reaction depends on the strength of the acid and base involved.
In the case of sodium hydroxide (NaOH) and hydrofluoric acid (HF), the value of their heat of neutralization is higher than the typical constant value because HF is a weak acid. Weak acids have a lower degree of ionization than strong acids, meaning that fewer acid molecules dissociate into ions in solution. As a result, the reaction between NaOH and HF is incomplete, and less heat is released compared to a reaction between NaOH and a strong acid.
To determine the specific values of the heat of neutralization for NaOH and HF, you would need to refer to experimental data or use thermodynamic calculations. Experimental measurements involve carefully measuring the temperature changes during the reaction and using the heat capacity of the solution to calculate the heat released or absorbed. Thermodynamic calculations can be based on thermodynamic properties like enthalpies of formation and standard enthalpies of neutralization.
In summary, the higher value of the heat of neutralization for NaOH and HF compared to the typical constant value can be attributed to the weakness of HF as an acid, leading to incomplete reaction and less heat release. The specific values can be determined through experimental measurements or thermodynamic calculations.