What is the standard enthalpy of formation (ΔHf°) for an element in its standard
Practice Questions
Q1
What is the standard enthalpy of formation (ΔHf°) for an element in its standard state?
0 kJ/mol
100 kJ/mol
298 kJ/mol
The same as its molar mass
Questions & Step-by-Step Solutions
What is the standard enthalpy of formation (ΔHf°) for an element in its standard state?
Step 1: Understand what standard enthalpy of formation (ΔHf°) means. It is the change in energy when one mole of a compound is formed from its elements in their standard states.
Step 2: Recognize that elements have a specific form they take under standard conditions (like temperature and pressure). This is called their standard state.
Step 3: Know that for any element in its standard state, the standard enthalpy of formation is defined as zero. This means there is no energy change when the element is formed from itself.
