Guest

The enthalpy of formtion of H2O(l) is -28070kjmol and enthalpy of neuralisation of a strong acid and strong base is -5670 kjmol what is the enthalpy of formation of OH-

The enthalpy of formtion of H2O(l) is -28070kjmol and enthalpy of neuralisation of a strong acid and strong base is -5670 kjmol what is the enthalpy of formation of OH-

Grade:12

1 Answers

SAGAR SINGH - IIT DELHI
878 Points
13 years ago

Dear student,

Enthalpies of Formation

Using Hess's Law we can calculate reaction enthalpies for a variety of reactions using tables of known enthalpies

Many experimentally determined enthalpies are listed by the type of process

  • D
  • H for converting various liquids to the gas phase are listed in tables of enthalpies of vaporization
  • D
  • H for melting solids to liquids are listed in tables of enthalpies of fusion
  • D
  • H for for combusting a substance in oxygen are listed in tables of enthalpies of combustion

The enthalpy change associated with the formation of a compound from its constituent elements is called the enthalpy of formation (DHf )

Conditions which influence enthalpy changes include:

  • temperature
  • pressure
  • state of reactants and products (s, g, l, aq)

The standard state of a substance is the form most stable at 298 ?K (25 ?C, or standard "room temperature") and 1 atmosphere (1 atm) of pressure

When a reaction occurs with all reactants and products in their standard states, the enthalpy change is the standard enthalpy of reaction (DH?)

Thus, the standard enthalpy of formation (DH?f)of a compound is the change in enthalpy that accompanies the formation of 1 mole of that substance from its elements, with all substances in their standard states

The standard enthalpy of formation for ethanol (C2H5OH) is the enthalpy change for the following reaction

Think You Can Provide A Better Answer ?

ASK QUESTION

Get your questions answered by the expert for free