6.1—The enthalpy change, ∆H, is the heat energy change measured at constant pressure and that standard conditions are 100 kPa

Know that the enthalpy change, ∆H, is the heat energy change measured at constant pressure and that standard conditions are 100 kPa and a specified temperature, usually 298 K.

Use —the enthalpy change, ∆h, is the heat energy change measured at constant pressure and that standard conditions are 100 kpa to connect the rule to the data and decision in the question.

This matters because —the enthalpy change, ∆h, is the heat energy change measured at constant pressure and that standard conditions are 100 kpa determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the enthalpy change, ∆h, is the heat energy change measured at constant pressure and that standard conditions are 100 kpa to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The enthalpy change, ∆H, is the heat energy change measured at constant pressure and that standard conditions are 100 kPa is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.