What do the symbols mean Delta Hr Hf Hc Hn Ha in chemistry btw i know theyre enthalpy changes?

Answer 1

delta Hr is the enthalphy change of a reaction

delta Hf is the enthalpy of formation where one mole of a substance is formed ( generally in its naturally occurring physical state)

delta Hc is the enthalpy of combustion where one mole of a substance in its standard state undergoes combustion

delta Hn is the enthalpy of neutralization where one mole of H+ reacts with OH- to form one mole of H2O

delta Ha is the enthalpy of atomization where a molecule splits to form its neutral atomic components

Answer 2

• ΔH: Represents the change in enthalpy of a reaction.
• ΔHf: Standard enthalpy of formation, which is the enthalpy change when one mole of a substance is formed from its elements in their standard states.
• ΔHc: Standard enthalpy of combustion, which is the enthalpy change when one mole of a substance is completely burned in oxygen.
• ΔHn: Standard enthalpy of neutralization, which is the enthalpy change when an acid and a base react to form one mole of water under standard conditions.
• ΔHa: Standard enthalpy of atomization, which is the enthalpy change when one mole of gaseous atoms is formed from an element in its standard state.