`HCI` is a strong acid, but HF is a weak acid. The enthalpy of neutralisation of `HCl` is -57.3 kJ `mol^(-1)` and of HF is -68.3 kl. `mol^(-1)`. Explain.

HF is a weak acid but HCl is a strong acid because

Bond enthalpy of bromine is 194 kJ mol^(-) . If enthalpy of vapourisation of Br_2 is +30 kJ mol^(-) , electron gain enthalpy of Br is -325 kJ mol^(-1) and hydration enthalpy of bromide is -339 kJ mol^(-1) calculate the change in enthalpy for the reaction, 1/2Br_(2)(l) + e^(-) overset(aq)(rarr) Br^(-)(aq) .

The standard enthalpy of formation of hypothetical MgCl is -125kJ mol^(-1) and for MgCl_(2) is -642 kJ mol^(-1) . What is the enthalpy of the disproportionation of MgCl ?

Assuming that, water vapour is an ideal gas the internal energy (Delta U) when 1 mol of water is vapourised at 1 bar pressure and 100^(@)C (given : molar enthalpy of vaporisation of water at 1 bar and 373 K = 41 kJ mol^(-1) and R = 8.3 J K^(-1) mol^(-1) )) will be

The enthalpy of formation of ammonia is -46.0 KJ mol^(-1) . The enthalpy change for the reaction 2NH_3 rarr N_2 + 3H_2 is

Heats of ionisation of acetic acid and ammonium hydroxide are x kJ mol^(-1) and y kJ mol^(-1) . Heat of neutralisation of HCl and NaOH is z kJ mol^(-1) . Calculate the heat when acetic acid is neutralised with ammonium hydroxide. (z-(x+y)kJ mol^(-1))

Enthalpy of neutralisation of H_(3)PO_(3) acid is -106.68kJ//mol using NaOH. If enthaly of neutralisation of HCl by NaOH is -55.84 kJ/mol. Calculate DeltaH_("ionization") " of " H_(3)PO_(3) into its ions