What is the standard enthalpy of formation for an element in its standard state?
Practice Questions
1 question
Q1
What is the standard enthalpy of formation for an element in its standard state?
0 kJ/mol
100 kJ/mol
298 kJ/mol
1 kJ/mol
The standard enthalpy of formation for an element in its standard state is defined as 0 kJ/mol.
Questions & Step-by-step Solutions
1 item
Q
Q: What is the standard enthalpy of formation for an element in its standard state?
Solution: The standard enthalpy of formation for an element in its standard state is defined as 0 kJ/mol.
Steps: 4
Step 1: Understand what 'enthalpy of formation' means. It is the heat change when one mole of a compound is formed from its elements in their standard states.
Step 2: Recognize what 'standard state' means. It refers to the most stable form of an element at 1 atmosphere of pressure and a specified temperature (usually 25 degrees Celsius).
Step 3: Identify that elements in their standard state are not compounds; they are the pure forms of the elements (like O2 for oxygen, N2 for nitrogen, etc.).
Step 4: Learn that by definition, the standard enthalpy of formation for any element in its standard state is set to 0 kJ/mol. This is a reference point for measuring the enthalpy of formation of compounds.
